Hiya,

In my completely unprofessional opinion (because I'm not a professional) I would say getting him on a better sleep schedule would be the place to start. I'm not sure if it's depression or not but if you're concerned about that you might want to take him to a psychiatrist. There are online tests you can take too that might help guide you in the direction of a diagnosis.

Hope you get this sorted out soon.

Love and hugs,
Tara