Does he act any differently when he is awake than what his parents are accustomed too? I'm wondering if he's effectively dealing with his issues on the subconcious level or if this symptom is part of a larger change in behavior that would conincide with repression.
I'd say let him be for the time being, but if his health starts to fall off than you can step forward and ask him to let your assist him. Not only will he be more willing to go along with it once the problem becomes more tangible, but you'll also have a better idea of what's going on with him based on the symptomes.
