oh dear, at sitting up at night. I know how annoying this is because although my LO cant sit up unsupported yet she can roll over onto her belly and try to crawl which is annoying at night in her cot because she gets stuck and needs turing over. Only for her to do it again, and again and again! Nightmare isnt it, and yes she finds it very funny when I turn her back over and decides its play time then and wants to make a game of it.