do you mean 'somersault'? OMG!!! my 16mth has been trying to do this recently!!! no one teach him at all, i think is 'self-taught'... my hub will entertain him and help him to roll forward. But my mum asked me to ignore him, dont help him, if not he will get used to it.
when we ignored him, he will try to roll on his own but usually fall sideway. and he will only do that on the bed, not on the floor. -.-"""