Gerald is careful. Piggie is not.
Piggie cannot help smiling. Gerald can.
Gerald worries so that Piggie does not have to.

Gerald and Piggie are best friends.
In Happy Pig Day! Piggie celebrates her favorite day of the year! But will Gerald the Elephant be include

A three-time Caldecott Honor winner for Don't Let the Pigeon Drive the Bus!, Knuffle Bunny: A Cautionary Tale, and Knuffle Bunny Too: A Case of Mistaken Identity, Mo Willems has also won two Geisel Medals for There is a Bird on Your Head! and Are You Ready to Play Outside? And his books are perennial New York Times bestsellers. Before he turned to children's books, Mo was a writer and animator on Sesame Street, where he won six Emmy Awards. Mo lives with his family in Massachusetts.