If he sleeps too much you really need to punish him for it. Unfortunately if you never punish him he will want to do everything way too much and basically act like a retard. Go into the creature cave and see if he says something like 'I am extremely tired'. This tells you that your creature will want to sleep a lot (although he might not actually sleep all that much if he is, for example, extremely compassionate, playful, and greedy too.