I know if I mark it tenant I am going to get some heat.
FHA considers it owner occupied if son or daughter lives in it. All in the immediate family.
(My bold.)"Owner-Occupied" means a one-to-four unit property owned by a borrower whose principal residence is a dwelling unit in that property.
Not an FHA. Son pays no rent. I am leaning towards marking it tenant, with a comment about who is living there. Don't know what the room mates pay or to whom.