Mo Willems est un auteur-illustrateur à succès qui a créé des livres classés au palmarès du New York Times. Il a été finaliste de la médaille Caldecott à trois reprises. Mo a débuté sa carrière comme écrivain et animateur de l''émission Sesame Street qui lui a valu trois Emmy Awards. Il habite au Massachusetts avec sa famille.

Mo Willems is the author of groundbreaking picture books, including; Knuffle Bunny: A Cautionary Tale (Caldecott Honor winner 2004); Don''t Let the Pigeon Drive the Bus! (Caldecott Honor winner 2003); Time to Say "Please"!; Leonardo, the Terrible Monster; Edwina, the Dinosaur Who Didn''t Know She Was Extinct.

In his previous life, Mo was a six-time Emmy Award winning writer and animator for Sesame Street and the creator of Cartoon Network''s Sheep in the Big City. He lives with his family in Brooklyn, New York.