Okay this is what I found out after playing the game for 5 days I've been playing with all the families to confirm my theory, when I started buying the house upgrade and praising them for using it. They stop being Exhausted, the problem got solved completely I'm serious. I think that they need to have these things in other to relax and do other stuff than work or do homework. Also they have to have a lot of food like all the time plenty of groceries especially if your family is big. Buy first the less expensive upgrade and proceed with the other item as money grows. But I’m almost 100% sure that this upgrades will solve the problem, Can someone else tell me if they've tried that already and it didnt work? I want to know if my theory is correct.