Until recently Everett expressed little interest in crawling. He has been able to sit independently for some time.  And he can stand for extended periods of time as long as someone helps him balance.  But he doesn’t really like being on his belly, and when he is he kind of flails his arms and legs around and makes unhappy noises.  Anyway, that changed a few nights ago when he started flipping over on the changing table.  He has become so adept at this (perhaps because the raised sides give him additional leverage) that we now have to change him on the bed or the floor, which provides plenty more room to perform 360 degree rolls.  And in the process of his he has started to pull his knees underneath his chest and make crawling motions.  This also means that we have to get serious about baby-proofing the house, something we have been meaning to do but have been making only slow progress on.