I wouldn't worry about it if I were you. My DS was still not weight bearing properly (i.e. he would only do it sometimes, and he didn't do it when we were at the MCHN) at 12 months. And he wasn't crawling. He had just started bumshuffling a few days before, and he only sat himself up from tummy to bum for the first time while we were at the MCHN.

Anyway, she referred us to a peadiatric physio. By the time we got in to see them, DS was well and truly bum shuffling and was much happier standing up. Now, at 16 months, he is cruising around furniture and even taking a few steps on his own. Given his very late development to even begin moving (he was never much of a roller either), he's doing much better than I imagined he would.

Oh, and the physio said we didn't have anything to worry about. Some babies just develop different things first. EG. DS has always been really good with fine motor skills.