Sometimes certain kids need little more support if they are filled with anxiety. For example I was 9 years old when my mom was in a coma and I was the one that found her (attempt od) I was so terrified and filled with so much anxiety when I learned that she will never ever come back. I had to sleep with my dad for 2 years because the extreme nightmares that I had and shaking and crying. Without a mom I was lost at the time and need more support than ever
If he does not have any problems that is hard to bare with himself. Have a good talk with him. Ask him why, does something scare you at night, how can we get YOUR room more comfy, etc. start with making him sleep in his room one night a week while licking your door at night to help teach independence at night