Sleeping, is essental to Miuchiz as much as it is to you. Whenever your not on your Miuchiz Handheld you just go to it's Bedroom and let it go to sleep. If you forget to bring it to sleep all of it's three bars the happy, fed and fun will eventually become red in a couple of minutes. The Miuchiz also moves in the bed a little if you leave it on for a couple of seconds you will see it. Sleep is important if your not playing on your handheld.