What Makes One Have The Habit Of Having The Fan And Central Air System On Even When It Is Not Really Necessary?

Hi! My 40 year old son is ALWAYS hot!!! Even in winter he wants to sleep with a window unit on all night!!! His 2 daughters, aged 10 and 11, are the same way. Is there a condition that causes this? In the Summer they sleep with central air going, a window unit, a ceiling fan, and a box fan!!