The 'Little Bill' series has been challenged on the basis of the sexual allegations against its author as opposed to the content of the books.

Bill Cosby’s Little Bill series is ninth on the list of the American Library Association’s top 10 challenged books of 2016. But unlike other books on the list, which have been flagged for their content, Cosby’s books have been challenged on the grounds of the sexual assault allegations against him, marking the first time this has happened in ALA history.

The series follows the adventures of 5-year-old Bill Jr. as he grows up in Philadelphia and learns a variety of lessons. The books were later adapted into an animated series of the same name which ran on Nick Jr. from 1999 to 2004.