I was just wondering how old was your bub when he/she started crawling (on all four's not on belly) and walking?

My baby is still commando crawling and sliding on her back by pushing her bum up at nearly 8 months and has only tried to get up on all fours on several ocassions. She can stand up on her legs when I hold her. She hasn't tried to crawl properly at all.

I read in a book that babies that crawl/slide on their bellies tend to skip crawling and go straight for the standing and walking stage.

Any feedback would be great.

Thanks!