Q&A: baby not sitting up yet

Susan writes:

"I have a baby who will be 6 months old in two weeks and I can't help worrying about his development.  He was very big and strong from birth (holding his head up and putting weight on his legs within weeks of his birth). We do some tummy time every day but it seems he isn't making much progress towards sitting or crawling.  He still completely topples over when he is in a sitting position (I mean completely - he does not sit unsupported even for a couple seconds) and he rarely rolls stomach to back (though he easily rolls back to stomach). Should I be worried? Aren't almost all babies sitting unsupported by 6 months?"

These milestones are a pain in my butt.

Because, yeah, it is helpful to know what's supposed to be happening when in a general sense so you can have realistic expectations (I remember thinking that a one-year-old could probably speak in complete sentences back before I had one of my own), but at the same time kids are so varied and variable that you can really make yourself worry over things that don't mean anything.

Remember, I'm not an expert (sooooo not an expert), but this is what I've gathered from parents of kids with serious problems, not-so-serious problems, and no real problems: The first thing to notice is how your child interacts with you. Is your child alert and mostly happy (unless they're going through a cranky phase)? Will /she make eye contact with you? Does your child smile/laugh? Is your child interested in things? If all these are true, then things are probably going to either be nothing, work themselves out, or be managed in a doable manner. If these things are not true, then please ask your pediatrician for a referral to get your child evaluated, because the sooner you can get information the better off you'll all be.

Now, to specifically address Susan's concerns: The rumor that almost all babies are sitting unsupported by 6 months has been greatly exaggerated. Some are, but a whole bunch aren't. Lots of times kids go from just lying there like pitiful, frustrated little lumps one day to crawling like speed demons and sitting the next. Sometimes they sit first. Neither of mine sat unsupported until several weeks after they started crawling (maybe I'm a bad person, but I thought the slow list to the side and then the topple was consistently funny). Some kids crawl for half a day and then start running. As long as the child is given plenty of tummy time and not confined in a saucer for too much time at a stretch*, they'll develop the way they're supposed to, which may not be on the Official Schedule.

I think that if he's alert and responsive and grabs for things and flaps his arms and legs and all that stuff, he's one of those kids who will crawl at 8 months (yay!) instead of 5 months (quick--babyproof everything in one day!).

Now, as a public service, we will all share how old our kids were when they crawled, sat up unsupported (if you even remember), and walked. Please state gender and if they had any special circumstances. I'll go first: My first boy was born big (9.5 pounds) and crawled at 9 months, sat a few weeks later, and walked at 14.5 months. He is a supergenius. My second boy was born smaller (8.5 pounds), and crawled at 8.5 months, sat shortly after, and walked at 14 months. He is also a supergenius. Both of them run just fine.

(I'm going to go out on a limb and predict that someone will say that her kid crawled at 5 months, and someone else will say that her kid crawled at 11 months, and if we put them next to each other at 3 years you wouldn't be able to tell the difference.)

* I've heard from a couple of sources that the benchmark for saucer time is supposed to be something like 20-30 minutes 2-3 times a day. Which is about as much time as it takes you to shower, and then get a decent start on a meal later on. Or eat an entire dark chocolate bar slowly while reading Entertainment Weekly. If you're saucer-addicted and want to try some options that give more freedom of movement, check out the article on 10 ways to make tummy time more fun from SparkPlugDance.org.

Comments

[enu]

Well, things may have actualy changed age-wise, since they flipped the position babies sleep in. Back in my day, babies had to be put down on their tummies to sleep (to prevent SIDS, dontcha know!) so the concept of tummy time was not an issue.

I don't have a clue when my two strange darlings sat, because they wouldn't. They certainly crawled and walked before they sat, but that's because if you put them in a sitting position they would tilt forward into a crawl immediately and off they went. Sitting still and playing with toys? What? Do you want Mom to get lazy???? The doctor would ask "is she sitting up yet" and I'd have to say "I don't know!" Then the doctor would sit the baby up and, well, off baby would go...
For the record, they both crawled at 5ish, firstborn ran at 10 1/2 months, walked at 11 months... (had neither sat nor stood still at this point) Lil sis stood still first for a while (one year) then walked at 14 months. (By which time she _was_ speaking in sentences, btw...!)

As for looking at them both down the road... Pretty much no diff, as you say. Although I gotta say the keep on moving baby did fly off to Paris by herself last week....

[Dani]

I'm the one with the kid who crawled at 11 months. She is, of course, a supergenius. :)

Seriously, at 5.5 months neither of my kids could do much of anything physically. The baby is almost 10 months now and as I type this she's rocking back and forth on her hands and knees trying to figure out how to make that thing GO.

[Pam]

Girl, 8 months old. Sat up around 5 months. Still falls over when her attention is caught and she swivels her head too much in one direction. Rolled from back to stomach (only to her left side), freaked out and needed to be flipped over. Has since decided she won't roll over (hasn't rolled over in weeks despite much prodding). She's pulling to stand now so I figure she's just going to skip the whole crawling thing - too inefficient for her purposes I guess.

[Shandra]

I - can't remember about the sitting. And once it was so important to me!

My son didn't crawl until 11 mos and didn't walk until well past 16 mos. He's 23 mos now and you cannot tell. He's working on jumping.

That said, my feeling about these things is that getting a quick checkup at the doctor's is a nice way to NOT spend two months stressing about it.

[robin]

My baby laid on his back all day long until he was over 6 months old. (OK, I gave him some tummy time, but he has a big head, so he hates it.)

He is 7.5 months old now and can sit unsupported for a little while, but he still topples over sometimes -- I have to make sure to always put a pillow (or myself) behind him. He has absolutely no interest in scooting, creeping, crawling, or cruising (though he loves to put his weight on his legs). He is perfectly happy to sit in one place and play with me, his dad, or his toys, and I am perfectly happy to let him!

And by Moxie's (wisely chosen) criteria, he is just fine. He is happy, healthy, playful, interactive, curious; he smiles and laughs and jabbers all day long.

I think the "all babies sit up at 6 months" myth is perpetrated by the same people who say "most babies sleep through the night by 3 months." Not my baby, and not most babies I know!

[Kate]

I also don't remember exactly when my daughter sat up - I think shortly after 6 months? I also worried about it, and we were told a) not to worry and b) to get a Bumbo seat, which is a great tool for teaching babies to sit. She loved her Bumbo and was so cute in it! But if your baby is big make sure to try it out first because some of my friends with bigger babies found their kids were not comfortable in them.

[Jennifer Barnes]

My firstborn is a freak of nature. He was sitting, unsupported, by 4.5 months of age (with a pillow behind him on the floor to catch his big cranium when he went over backwards), pulled up at 6 months, crawled at 8 months briefly, and was walking at 9 months. Now he's 2 and just like all the other 2 year olds so I don't know what the big rush was.

My secondborn is 4.5 months old and content to just be a blob. He doesn't even roll over! But, like Moxie said, he smiles, makes eye contact and is interested in moving objects (any motion!) and I'm not at all worried. yet.

[paola]

With my first male, i realised he could sit supported when i put him for the first time in a high-chair at 6 months. It took some more time ( about a month) before he could sit by himself and then he kept falling every which way for quite some time. He crawled at 10 months and walked at 15.

My daughter is 6 months and a week old and is sitting qiute well when supported, but topples over when I stop supporting her.

[AmyinMotown]

My memory of this is fuzzy, but I am pretty sure she wasn't sitting up by herself at six months--she's got a ginormous head and was army crawling at 5 months but I am pretty sure not sitting by then. And she got lots of *floor torture* AKA tummy time. I do remember a pannicked call to the pediatrician because she was sitting and just flopped over, HARD, banging her head on the hardwood floor.

She's two and a half now, also a supergenius and amazingly beautiful besides :-), and runs (Okay, it's a goofy run, but still) everywhere she can. Her reacher has expressed some concern about her droppig things and tripping a lot, but I kind of laugh and say that both her father and I are majorly klutzy so I would expct the same from her.

[AmyinMotown]

TEACHER. Not reacher. Speaking of klutzy.

[flea]

Both my kids, one girl and one boy, both 8+ pounds at birth and on the big end of the growth charts, could not sit unsupported at 6 months. Maybe 7.5-8 months for true mastery, with some flopping even then (heck, the boy who just turned one fell over and whacked his head on the floor from a sitting position this weekend). Both crawled at about 9 months; the girl walked at 13 and the boy just turned one and is cruising but not walking. Anecdotally, I think bigger/big-headed kids sit and move later.

We used a boppy pillow to help with the slouch-slump-bonk problem. Which is definitely comical. Also carrying them upright on your hip helps develop trunk strength (theirs and yours!)

[Katy]

My son was never good at tummy time, only rolled over about twice around 4 months and was sitting up well by about 7 months. Then he commando crawled around 9.5 months and went up to proper crawling around 11 months. He's now 13 months and is pulling up and cruising a tiny bit, so he's not going to walk on his own any time soon. So he's always been a bit slow on the gross motor skills, but he's such a happy, laid-back baby, I just don't think it bothers him to not be able to go places!

[Nutmeg]

The littlest bubs was a peanut at birth (6lbs). At 6.5 months he weighed 17 lbs. He lifted his tiny little noggin off my shoulder when he was <24 hours old and was holding a bottle at daycare when he started (never really having seen a bottle before) at about 3 months.

He rolled from back to front and then from front to back intentionally within weeks of eachother at about 4 months, and promptly refused to perform the task ever again.

He despises tummy time and we do it every day but very little (the specter of the 3 months of colicky baby = not wanting to elicit any unnecessary crying)

He's been sitting supported from about 4.5 months and by exactly 6 months we stopped putting "just-in-case" pillows behind him because he was really unlikely to tip/topple. He DOES do an admirable yoga thing where he leans forward and sucks on his toes while sitting.

He's 7 months old and despite being VERY STRONG couldn't care less about moving.

I think sitting's got nothing to do with anything.

Oh.. and he had a good time sucking on my toe this morning... but even so I'm pretty sure my kid's a super-genius too. :)

[fahmi]

My son was born average, I guess - 8 pounds 3 ounces, full-term. He started sitting unsupported at a bit before 5 months, but he was always leaning forward. He got strong enough to sit up a few weeks later, and started commando-crawling (crawling, but tummy on the floor) around 6 months. He started "real" crawling at about 9 or 10 months, and then started walking a week after his first birthday.

[3maybemore]

My three are all girls.
DD1 sat 7.5 mo crawled 10 mo walked 15 mo

DD2 sat 5 mo crawled 7 mo walked 15 mo

DD3 sat 7 mo is currently 9 mo and not crawling.

[Erika]

I have one of those freaks of nature - which, after reading all of the other responses, just goes to prove that all babies are different and it just doesn't matter. My girl started rolling at 3 months, crawling and sitting up at 6 months (same day), and pulling up to standing and doing some cruising at about 6 and a half months.

FWIW, she hated the bumbo - wouldn't let me sit her in it. Also wouldn't let me sit her propped with pillows, or leaning up against me. She had to be standing up - and she'd cry 'til I held her up so she could stand. (Now that she's so mobile she's happy to sit for a spell ...)

[Katy]

My son was born 3 weeks early and was only 4lbs 11oz, but grew quickly. I'm pretty sure he couldn't sit unsupported until he was around 7 or even 8 months. For a while after that he would sometimes fall over and conk his head on the hardwood floor, so we made use of the Boppie and pillows for awhile.

He pulled himself up and was cruising at maybe 10 months (amazing how quickly you forget these dates/milestones!), then crawled at 11 months, and walked at almost 13 months. He did love the saucer, so who knows, maybe that slowed him down a bit. But he's now 18 months and practicing running and working on some climbing.

[Liza]

I also had a 9.5 pounder, a boy, who has stayed at the high end of height for all of his 17 months. Being breastfed, still, he's leveled off to the middle of the weight range.

Thank goodness for blogging, or I would only have been able to remember the walking one. All of these were +/- about a week.

Sat Up: 6 months
Crawled: 7 months
Stood: 9 months
Walked: 1 year

[meghan]

Cole starting sitting independently, and never really fell over at all, at 5 months.

He crawled at 7 months, and starting cruising the next week.

At that rate, everyone assumed he would walk at 9 months. 6 long months later, he began taking multiple steps at 15 months.

You really never know what you're going to get.

[Megan]

My son sat at around 5 months, crawled by 9 months and walked at 13 months. Lots of people asked me, "He's not walking yet??" but I didn't care. I knew he'd do it on his own time.

On the kids who go from not crawling straight to walking: my pediatrician was happy with how long DS crawled. He said that crawling is very important for eye-hand coordination, and if your baby is trying to cruise before he/she'll crawl, you can move the furniture around so that he/she has to crawl. (I only have one kid so far, so don't have much anecdotal evidence on this, but my son does have very good eye/hand coordination.)

[lisa]

My son was born at 37.5 weeks and weighed 7lbs 7oz. I think he sat unsupported around 7 months, started pulling up on the coffee table around 9-10 months, crawling around 11 months. Almost never rolled over (HATED tummy time). Now he's 15 months, crawls like a demon, so of course has no interest in walking. He cruises on everything, but doesn't stand unsupported & if you hold his hands (which he doesn't like), he'll just bend his knees to sit down. But he's resisted everything he was "supposed" to be doing, until the day when he just did it, like he was born doing it...crawling, weaning from bottles to cups, etc. I figure it will be the same thing with walking & talking. We'll see what the pediatrician says.

[z]

My son sat up unsupported (with my help) at just over 5 months. He sat up on his own at 6.5 months, started crawling (instead of scooting) 2 days later. Started pulling himself up the day after he started crawling. At 10 months now cruises around holding onto furniture, walls, doors. He has let go occasionally (which leads to 2 seconds of standing and then a crash) but for the time being is content holding onto stuff to move about.

[Arwen]

My daughter weighed 7 pounds at birth. Could hold herself consistently in a sitting position at 6.5 months; crawled at 8.5 months. Rolled over front to back at 5 months, and back to front at 7 months, and I'm glad to see I'm not the only one whose kid rolled over a few times and then refused to repeat it. At just over 9 months my girl has finally reached the stage where she can roll from front to back and get herself into a sitting position easily, which is great for me because she doesn't need me to rescue her so much. On the other hand, that thing where she'd crawl a little bit and then flop onto her tummy and look at me helplessly was pretty cute.

I can totally understand Susan's stress, although her kid sounds totally normal and a lot like mine, milestone-wise. I have to stay away from those charts or I turn totally obsessive and forget to enjoy my baby because I'm so concerned about what she is and isn't doing. And she's fine. As is Susan's baby, I'm sure.

[Maggie]

I also have a 'big and strong' boy, and although he's not old enough to compare with yours yet, our pediatrician told us he would very likely be "behind" on some of the milestones...that when they're bigger it takes more muscle development for them to be able to do some of those things.

[Katie]

Cricket is a huge kid. We'll find out just how huge this week, but I suspect he's over 20 lbs.

He sat up on his own for an extended period of time exactly on his six month birthday. Cricket was also 5 weeks premature, but I suspect he caught up quickly. Apparently we are to use his adjusted age for a year? But if we do that then he's even more of a bruiser. He sits now but throws himself backward a lot or topples forward, so he's always supervised.

He has no, none, and zilch interest in crawling. Nothing puts him a worse mood than being on his stomach.

I freaked out a little because at a book club someone said that crawling was necessary for neurological development. And what if my kid never wants to crawl? He'll scoot backward on his back, but crawling? Nope.

I have to pray/meditate every day in order to not be crazed about milestones.

[Charisse]

Mine's a girl, born 7 lb 14 oz.

Sat unsupported at 5 mos
Rolled both directions at 6 mos
Crawled at 12 mos
Pulled up at 13 mos
Walked at 15 1/2 mos
Ran at 18 mos

She was born average but has been big since, and continues to do physical stuff on the slow end of the normal range, but always well once she gets there. We worried when she turned one w/o crawling or pulling up (esp since we knew a bunch of crawl at 7 months babies), but her pedi said give it another month...sure enough, 2 days later she did it, with correct traditional form.

She's 3 now, you wouldn't know the difference.

[Sarah]

My daughter and son both started an 6 lb 9-10oz. Both were breastfed. She grew enormous and chubby. She sat at 6 month, crawled at 7 months, walked at 10 months (And I thought she was slow because I walked at 9 months). At 5 year old, she is still 90t percentile in height and weight.

My son stayed lean. He crawled at 6 months and sat at 7-8 months. He had the "why would I sit?" look down cold. He walked at 13 months. He has stayed lean, at 3, he is 50th-75th percentile for height and 10th percentile for weight.

Neither of them talked anywhere near "on time" and we had speech therapy in our lives for years. So the physical milestones didn't comfort me as much as they might have. The milestones charts are usually aggravating.

[amy]

My daughter was born at 35 weeks, weighed 3 lbs, 9 oz. She sat supported at 4.5 months, but she was still needing support (or at least some surrounding pillows) at almost 8 months. FWIW, she also developed severe anemia sometime after 6 months, but as soon as we got going with supplements and treatment, she zoomed forward. She always, ALWAYS hated tummy time, probably because of her ginormous head; she never crawled; she walked at 12.5 months. She is, naturally, a supergenius. ;)

[Sonia]

My son was 7 lbs 7 oz at birth, sat up around 6 months, and started crawling around 7 or 7.5 months. Then he did the downward-facing dog yoga pose for a while as he was figuring out how to pull up. Between 11 & 12 months he started walking and is now unstoppable.

I was so worried when I read in the "What to Expect" book about possible problems from too much Exersaucer time that I never kept my son in it for more than 15 minutes or so, maybe once or twice a day. (What can I say - 1st time parent & took everything I read too seriously). Now I wish I'd made better use of it back when he enjoyed it. Alas, now he protests if he's confined for more than 5 minutes. Makes it tough to take a shower if I don't manage to wake up before he does!

[Awesome Mom]

My eldest son was sitting by 8 months but not very well and he coudl not get into that position by himself. He then had a stroke and needed physical therapy. His therapist said to let him roll around and get as much tummy time as he would stand which would strengthen his back muscles.

I applied that to my younger son when he came along and he was sitting at 6 months, crawled not much later than that and was walking at 1 year. Don't rush it and don't force the poor kind into sitting when the back muscles are not strong enough.

[Blanca]

My son sat around 5.5 months. Roll both ways at 6.5 months. He started crawling backwards and turning at 8 months and last week (9.5 months) started crawling forward. Only army style though, he's still working in the all fours position.

But he's been able to pull himself up holding our hands since he was 6 months old and started using the furniture to do so right before turning 9 months. And he's working in his steps too.

If everything else goes ok I wouldn't worry. Every baby has its rhythm and it's not the same for everything.

[Jessica]

Stats on my super geniuses:

Girl Baby was born at 38 weeks and weighed 8 lbs 6 oz. My FIL "taught" her to sit up at almost exactly six months. We were on vacation together and he worked with her at it over the course of four days until she could do it. His idea--he was very sick at the time and so we let him do whatever he wanted with her. Before the vacation when placed in the sitting position she would immediately flop over so that her hands touched her toes and stayed that way. After the vacation she would sit happily unsupported and play with whatever was around her. She did not start trying to get from sitting to her stomach and back until 8.5 months. She started crawling at 9 months, began walking at 11 months and running by about 13 months.

Boy Baby was born on time at 9lbs 11 oz. He started to slither crawl (very fast) at 5 months, actually crawled at 7 months and cruised at 8 months. He did not sit up AT ALL until he was at least 10.5 months old. Starting at about 3.5 months, whenever he was put in the sitting position, he immediately flopped forward and either began attempting to crawl (months 3-5) or actually moving. I expressed concern at the 9 month appointment and the ped tested him by putting him in the sitting position and seeing if he would put a hand out to steady himself before he began crawling or pulling up. He did and she pronounced him technically able to sit up but just unwilling because he was much more interested in being mobile. He walked at 11 months and started running within 3 days of taking independent steps. At 15 months, his major preoccupation is trying (unsuccessfully so far thank goodness) to try and climb out of his crib.

[Sarah]

My daughter sat unsupported at about 5 months, crawled at 9 months and walked at 12 months. Here at 16 months, I'm still waiting for her to call me "mama" (language skills do not seem to be her forte).

[Nikki]

This is similar to an issue "we" are struggling with in our family right now. First, the basics:

First boy, born full term at 7lb 9oz, crawled at 5.5 months, pulled up at 7 months, walked at 9 months, ran at 9.5 months, somersaults at a year :) Now 3.5 and in gymnastics class just to give him a safe place to do all his crazy stunts

Second boy, born full term at 8lb 12oz, crawled at 5.5 months, pulled up at 8, now will be a year next week and stands on his own but has little interest in walking.

The reason "we" are having an issue with it is that everyone who remembers our firstborn walking early constantly berates me (ok, maybe berate is a bit harsh) about when secondborn is going to walk. I try to remind people that they are not the same baby and that whenever he walks is great with me, there's nothing wrong with him, but they just don't get it! I constantly have to fend off suggestions of how to make him walk sooner. People! We're not in a hurry here! Relax!

I think the difference is personality related in our family at least. Our oldest is outgoing, energetic, some might even say hyper. Our youngest is laid back, contemplative, just happy to watch his brother do cartwheels in the living room.

Bottom line, if your baby is not meeting those crazy timelines and your pediatrician is not concerned, you shouldn't be either :) It will all come with time! And like Moxie said, at 3 no one will care how early she crawled, sat, walked, etc! Oh - one piece of advice our pediatrician gave us: You can read all the books you want but just remember that your baby hasn't read them :)

[Rayne of Terror]

My son was 7 lb 10 oz at birth and holding his head up from day one. He was pulling up on the coffee table at 5 months, crawling just before 6 months, but DID NOT sit unassisted until almost 8 months. Then he was walking at 11 and now he's a physically normal 2 1/2 year old.

[Lisa]

I worried about my petite DD's development A LOT. I compared her to my nephew who is 6 months older than her and when their development didn't coincide it made me worry like crazy. She sat up without support at 8 months old, army crawled at 10 months, pushed herself into sitting and started pulling up and cruising at 11 months, traditionally crawled at 12 months, started taking steps at 15 months and FINALLY has begun walking now at 17 months. I really wish I hadn't agonized so much over her physical development because it was a big fat waste of time. Not only that, but I have since seen so many babies that aren't sitting unsupported 100% of the time at 7 and 8 months.

I hated reading message boards where people were like "My 7 month old is walking!" because it always made me feel so bad, but I promise you, when you hear people say every kid is so different, it really is true. I think your son totally sounds within normal limits.

[Carmen]

My little boy was 3.21kg (sorry - I'm not a lb person...) at birth, started rolling over (and then rolling everywhere!) at about 5 1/2 months, then crawling (commando style on his tummy) at about 8 1/2 or so, and sitting completely unsupported at about 9 1/2 months. He's now 11 months and stands/ walks around chairs, but never got into crawling on hands and knees. He seems to get around fine, though (almost a bit too well for our messy flat....).

Oh, I also never bothered (well, kinda kept forgetting... does that make me a bad mummy?) about tummy time.

[sm]

my sprout was 7lb 12 oz (girl), but has always been the biggest and tallest girl in her group since. i worried when all our friends were rolling and sitting proficiently in the 6 mo. range and she was doing NOTHING. she was never a 'saucer girl, but i wasn't a champ at giving her tummy time. much to my surprise, she started scooting one day (around 6 1/2 mo.), and within the next three weeks sat up, started to properly crawl, then learned to independently pull up. she's now 9 mo. and is like a bolt of lightning! point is, i do believe babies gotta do their thing in their own time.
it's always hard not to worry. if possible, cherish the non-mobile time. once it's gone, life is busiern than ever.

[Annika]

A lot of these are guesses, because I was totally unconcerned with milestones. He sat up somewhere around four or five months; crawled on his belly between five and six, and crawled upright on his seven month birthday (that one I remember); walked at a year, after taking tentative steps for about a month. Oh, he was just under 8 pounds at birth and held his head up the moment he was out. Weirdo supergenius baby.

[Anna]

my little girl was 1week overdue, weighed 7 lbs 5 oz at birth. She was breastfed until she was 14 mos.

4 mos - rolled from back to belly
5 mos - sitting up by herself
5 mos - could roll from back to belly and to back again
6 mos - commando crawling queen!
7 mos - crawled on all fours
10 mos - walked (was on Christmas so it was a present for me!)
...and hasn't stopped moving since!

she's only at 21 lbs at 16.5 mos but doc says she's perfect (to which i agree :o) )

Funny that she's so petite when me and dad are not at all (we're both tall and, ahem, fluffy)

[Charisse]

It's funny how much power these things have--still, 2 years later, reading about all of these 6-9 month crawlers very quickly brings back the anxiety I had when Mouse wasn't hitting that milestone.

Susan, we so understand where you're coming from! We all say it's OK now--and it is, and will be for you--but also know that the way you're feeling is normal, normal, normal.

[Cat, Galloping]

My son was born at 9lbs 1oz, sat up at 7 months (I believe), crawled at 9 months, and walked at 15.5 months.

[Helen]

Girl, born 5 lbs, 12 oz, 40w3d.
We never really did tummy time because she didn't like it, but she was frequently worn in a semi-upright position.

Sat unsupported a few days after 6 months.
Learned to sit up on her own from lying down, 8 months.
Crawled a few days after 9 months.
Walked a few days before 12 months.

Each new thing is literally out of nowhere. One day I sat her down in front of me, and she stayed up, like she'd been doing it forever. I believe giving her metal mixing bowls to bang on may have added a little incentive. Just when you start to get good and worried, or jealous of all the other babies in playgroup or whatever, bam, there you go.

[Jan]

Daughter, average weight at birth, was sitting unsupported by 7 months, but I think not at 6. Crawling ... can't remember, but maybe 8 months? Nine? Took her first steps on 11 month birthday and was running by 12 months. She's very bright, has always been great with large motor skills, seriously lacks in small motor skills and lags behind a bit socially.

Son, also average weight at birth, started sitting unsupported at about 7 months, crawling, pushing himself into a sitting position and pulling up into a standing position all in a one-week period at 8 1/2 months. First steps at 11 months, but not really walking until a year. He's more average with large motor skills and definitely more tentative. At 18 months he's still only using a few words, but is well within the range of normal.

I find one useful thing about the milestones. I use them to better understand where my kids fall in the spectrum. For example, I know that my Munchkin is ahead of the average kid in the communication department, but behind in small motor skills; I know that the Little Dude is tentative with large motor skills, but somewhat ahead socially. This helps me pick activities for them that will challenge, but not overwhelm or frustrate them.

I definitely agree that what is 'average' has probably changed since we started sleeping our babies on their backs instead of their tummies, and I'm not at all sure the 'experts' have updated their milestones to accommodate.

[Jan]

Oh, something to add now I've read other people's comments:

My younger brother never crawled. He rolled to get around, then went straight to walking. And his hand-eye coordination has always been just fine. He's a freakin' logical genius and a natural athlete. So there's that.

[carmie]

My son was 8lb 10 oz at birth. He started off on the big side and then we had a horrendous time starting breastfeeding and he dropped into the 5th%. He got back up to healthy and now sits in the +100% for height and 30% for weight. How's that for a crazy span?

Not much Jumperoo or tummy time (loathed it in spite of his small head), lots of being worn. He sat up out of the blue around 7 months, crawled at 10, and started running around 13 months. He's way off the charts for verbal skills and absolutely normal on fine/gross motor.

Susan, I bet he sits up on his own within a week of this post!

[Kate]

Child 1 (girl, born 8lbs 11 oz):
rolled both ways by 4 mos
sat at 5 mos
did downward-dog for 6 weeks trying to figure out how to crawl
crawled at 7 mos
walked at 12 mos

Child 2 (boy, born 7 lbs 12 oz):
rolled both ways by 2.5 mos
up on hands and knees; pivoting and slithering at 5 mos
crawled at 5 3/4 mos
sat and pulled to stand at 6.5 mos
walked at 13 mos

Neither have been on the early side for speech, though. That's a whole other kettle of fish, but I'm not worried. The three year old could talk you to death...those extra few months in which she just signed were just lulling us into complacency.

[Ally]

My son pulled himself up to standing, sat himself up from a lying down position, and crawled, all on his 7-month birthday. In that order. I don't remember when he was able to sit unsupported, probably a month or two before all that. He walked once, on his 9 month birthday, and then not again until around 10 months. He was 6 lbs., 13 oz. at birth and is, of course, a genius at almost 3. :)

[Kelly]

#1, born 3m early (and has always been tiny) with loads of complications and tons of worry about developmental delays, pulled himself up to standing at 10m and cross-crawled a week later and made it up 6 stairs a week after that. I don't remember when he sat because he never stopped moving long enough to do so. He didn't walk until a few weeks after his 2nd birthday. A month after his 2nd b-day he learned the entire alphabet (both capital and lower-case letters, right-side-up and upside down) and how to count to 10. He's an enigma (but we don't hold it against him).

#2 is now 7mo (and is a very big boy) and sat at almost exactly 6mo and has just started the transition between army and cross-crawling (Lord help me!).

Because so much of our parenting has been influenced by Early Intervention (#1) therapists, both boys have had loads of tummy time and zero time spent in exersaucers/jolly-jumpers/walkers (they're bad for baby hips and slow the development toward walking). One took his time, one's off like a shot.

[Terranova]

My little boy weighed 7 pounds 12 ounces when he was born at 41 weeks. Didn't want to come out! He sat unsupported at 5 months but didn't crawl til 10 1/2 months. He is now almost one year old (on Friday!) and isn't walking yet but sure cruises pretty fast!