when your kids fall asleep in the car for a nanosecond, then miraculously don't need a nap once you get inside

Took Moo out this morning and he was soooo tired, shut his eyes briefly as we got down our street. Of course now he's in bed he's having a grand old time in there! I've been listening to him muck around for about 45mins now and I think I'm fighting a losing battle.

Drats.