I'm not exactly worried.... oh go on then, I am! DS is commando crawling and rolling around. He'll be 11 months next week and he can't get from lying to sitting or vice versa - it's not that he doesn't want to, he just doesn't seem able to. Even if I put something a bit further away that he really wants, he kind of twitches his legs around and then cries. I've tried just leaving him and hoping frustration will get him to move, but it really isn't working and I can't leave him for that long because it just seems so mean. He bears weight brilliantly & has done for months - is desperate to stand and walk. Though not desperate enough to be able to pull himself up to standing. Anybody else had this?