When the light was on and all, I sort of looked at her for a while. She was laying there asleep, with her face sort of on the side of the pillow. She had her mouth way open. It’s funny. You take adults, they look lousy when they’re asleep and they have their mouths way open, but kids don’t. Kids look all right. They can even have spit all over the pillow and they still look all right.

J. D. Salinger

The Catcher in the Rye. Chapter 21, when Holden sneaks back into the family home to visit his sister Phoebe. She looks funny to Holden sleeping with her mouth open, whereas adults in that position look “lousy.” Phoebe represents the innocence of all children to Holden.