This is a post from Mama:
Dustin and I just got home from Anson, and Sam didn't sleep on the way home. So I fed Sam and put him in his crib for a nap. About 15 minutes later we hear screaming coming from his room
(He has started doing this when he gets excited.) This is what Dustin found when he walked into Sam's room.
He's so proud of himself for pulling himself up. I think it's time to lower the matress!