A.C.
Give him a special stuffed animal to keep him company at night. Let him know that if he wakes up at night, all he has to do is hug his animal and close his eyes. If that doesn't work you could always try bribing him. That's how I got my DD to stay in her bed. She started in a twin bed when she was about 18 months (kept climbing out of the crib & falling). Anyhoo, we hit a rough patch with her where she was sick & sleeping with me. When it was over getting her to stay in bed was a bear. I bribed her with fruit snacks. "If you stay in bed ALL NIGHT LONG, I will let you have these fruit snacks tomorrow after breakfast." It worked like a champ! After a few weeks it was the routine & there was no need to bribe anymore. It just got the ball rolling for us. Good luck & nighty-night!