So how is he still getting enough food to maintain his weight?  Since his parents are both hams, I bet meals at his house are disgusting.  They don't take care of themselves, so why would you expect them to take care of their own child?  I bet he asks for food all the time and they just give in because they're too lazy to be good parents.  The locks on the cabinets and fridge won't help if you're still feeding your kid too much food.