I need some help! My 4 month old has been really good up till now with lying slightly propped up on a pillow on the sofa so he can look around, see me, the T.V etc. He was also good in his bouncer, the problem is that now he seems to want me in view all the time and is starting to try to sit up more and more. With this mixture of things I am worried about leaving the room with him on the sofa in case he falls off by trying to sit and losing his balance. The bouncer chair is OK when I'm there but the other day I came back in and he was sitting that far forward I thought he might topple over still in the chair. What I really need to know is when is he old enough for a walker, or would a baby nest be more appropriate, also if I invest in a baby nest will he bother with it for long because finances aren't that great that I can waste money on something he will not use. Help!