Out of the Crib

I've been waiting for this day and it has finally happened; Will climbed out of his crib. I realize I've been very lucky since many children climb out much earlier than 21 months. Unfortunately Will was taking a "time out" and all of a sudden I heard his feet hit the floor and him running to the door (thankfully he didn't hurt himself). I stopped him as he was trying to open the door. Then reprimanded him and put him back in the crib. He didn't climb out again. I cannot believe it's already time to start thinking about a big boy bed!