DS is 9 months old today!! For the past few days he has been taking all of his toys and putting them on his head. It's just too funny. He has recently figured out peekaboo and when we're laying in bed he takes the sheets and covers his head with them so I don't know if he's trying to do the same thing with his toys or what. Is this toy on the head thing some sort of developmental thing or is he just being silly?