My First Knock-Knock JokesA silly collection of knock knock jokes so funny, they will knock your socks off! The goofiest, silliest, funniest knock knock joke book for kids (and that's no joke)! Get ready for a knock knock knockout with this hilarious book of fun! Filled with hundreds of the funniest, family friendly, rib tickling jokes and cool doodle illustrations, My First Knock Knock Jokes is the first BIG collection of silly, easy to read knock knock jokes for kids.