Peter lifts his legs up into the air.
He will hold things in his hands for long periods of time
(I may or may not have put that there).
Or he will figure out how to fling it out of his hand.
It's very exciting that he will notice and stare at things now.
I noticed Peter grabbing the back of his head the other day. It looks like he's thinking and instead of rubbing his chin he's rubbing his head.
That cool ball was sitting on the tray in front of him but he grabbed it all on his own. He made various attempts to get it into his mouth but alas it's bigger than his head so he had no luck there.
He actually enjoys tummy time now.