What age did your little ones sit up unsupported? DS is 7 and a half months and still can't sit up by himself, he's also only now starting to roll over to his belly but will only stay there for a few seconds and goes straight back on to his back. I know they all develop differently but would like to know a rough age, all my friends babies are sitting and crawling and I feel like somehow it's my fault that he's not doing it yet and that I should be doing something to help?