This document provides biographical information about children's book author Mo Willems and summaries of some of his most popular books. It notes that Willems was born in 1968 in New Orleans and started his career writing for Sesame Street before publishing books like Don't Let the Pigeon Drive the Bus. Some of his most well-known book series include the Pigeon books, Knuffle Bunny, Elephant and Piggie, and Cat the Cat. It provides short summaries of stories from several books in these series.