T.C.
Hi C.. My cousin and his wife had this problem with their children. They decided that instead of them sleeping with he and his wife in thier room, he and his wie would sleep in their room. My cousin made a pallet by his bed and slept there every night. Each night though, he would move his bed a little farther from the kids beds. Then eventually he was in the hallway. Then he was back in his own bed. It took about a week to a week and a half, but his kids were in their room and unafraid.
Also, try taking him and letting him pick out a special lamp. A dimmer or touch tone lamp works great. Then each night-turn it down a bit-until it is only a soft glow in the room.
My son has a special car bed that he sleeps in occasionally-he has a big boy bed as well. we left his toddler bed in his room since he felt protected in it.
Good luck with his sleep situation. Hope it works out well for you.