The start of a terrible habit?

This morning I heard a cry over the monitor. It was 5:00, so it had to be Jack. He wakes up every morning at 5:00, and I have to drag myself out of bed and put him back to sleep until 6:00. I call it his "preemtive wakeup". He is just getting me ready for the real thing at 6:00. When I drug my tired body into the nursery this morning though, I saw something different. Jack's eyes were closed, he had broken out of his swaddle, and he was sucking on his hand. I decided to slowly back out of the nursery and see what would happen. He put himself back to sleep for an hour! I think he has been aiming for that thumb, but hasn't quite gotten it yet. Right now any part of the hand will do.
My mom claims that I started thumb sucking at six weeks. She didn't mind this because I could soothe myself to sleep, and I became a "good sleeper". Now for the bad part...I had braces for five years. So after $5,000 worth of orthodontia bills she reconsidered how great that habit really was. I will tell you that I will take $5,000 worth of bills to get this kid to sleep. Heck I'd pay twice that for a good night's sleep. So we'll see. One night does not make a habit, but it just might. And maybe I'll get some sleep too.