D.L.
All three of my kids went through this and it only lasted a week or so. I would go in and put them down once and then if they did it again I would let them cry for longer - maybe 5-10 minutes before going in again. Each time I would make them wait longer in between and they would start to realize that it was better to stay down. If you go in right away every time then they start to use it as a way to get you to come in the room whenever they don't want to sleep. In a week or so he will probably learn how to get down and this won't be a problem anymore, I hope! Good luck! D.