I wouldn't worry too much, babies all develop their skills at a rate that suits them, not suits our expectations.

My DS didn't sit until he was 7 months (to the day) and isn't walking. We aren't worried about it too much. My DH always says that the more time they are taking to learn that stuff, the more time they are spending on developing their brain ie. will be more intelligent.

Probably not one truth in that, but makes me feel better when I see a 9 month old at daycare walking on her own and my 14 month old won't!!!!!

No point in comparing because you just feel low. And DD wouldn't want you to feel bad. So try to cheer up!!!!!!!!
We are all in this together - doesn't matter what stage we are at, as long as they can walk on their own or go to the toilet when they are 15