Whenever Robert seems to be tired or cranky, especially when it's the afternoon, we tell him that he needs to go take a nap. But somehow he has learned to associate this with the fact that he needs to cheer up and he won't be "punished" to go take a nap. So when we tell him that he soon will go to sleep, he says: "I'm happy" and automatically puts on a happy face, with the cutest smile you could imagine. Even sometimes he says "I'm happy" through his crying tantrum. It's really really really cute!