Where Butterflies Sleep

Allison, at bedtime: How come towels don't have to go to sleep?
Me: Because they're not alive. Only living things sleep. Now go to bed.

Allison, a few nights later, at bedtime: How come living things have to sleep?
Me: Because their bodies need rest, and their brains need rest. And you know what else? You grow while you're sleeping!
Allison: Well, where do butterflies sleep?
Me: Um, in trees, mostly.
Allison: And in their chrysalis?
Me: Yes! How did you know that?
Allison: I just knew it. And you know what happens when they sleep in their chrysalis?
Me: What?
Allison: They turn into butterflies!