We've learned to stand up and walk around coffee tables, adult legs, and most important, we've learned to stand up in our crib. The mattress is now lowered to its lowest possible level. Little Philip is so proud of himself he stands in the crib squealing to keep himself awake instead of falling asleep like a good little boy. Renie crawled in on her hands and knees with the camera after an hour one night. When she looked up, this is what she saw.