Rock Solid Sleep in the Crib

Joe put together his crib so Andy moved out of his almost outgrown bassinet to his real bed. I was anticipating a few days of long hard cries for adjusting to the new bed and his own room, but much to my surprise, Andy adapted right away. He woke up once the first night, and then I learned he could go back to sleep on his own quickly the next night so didn't go in any more. He has been sleeping through the night for the last few weeks. Sometimes he wakes up once or twice around 12 or 1, but can always go back to sleep after a few minutes of crying. Sometimes he wakes up between 6 and 7am then I'd feed him and he goes back to sleep for a couple more hours usually. I get up to pump a couple times at night to make him a couple extra meals for the next day (supply is all caught up with demand now). He seems to sleep comfortably on a real mattress: all stretched out (see pictures).