KNOCK KNOCK BOOK Guaranteed to leave you in stitches!If you can't resist shouting out "Who's there?" on cue, The Everything Kids' Knock Knock Book is for you! Features hilarious sections such as:Once Upon a Knock KnockWhen Fun Comes a Knockin'Tied Up in Knock KnocksKnock Knock Your Socks OffWho's That Knockin'? Packed full of puzzles, games, and activities, The Everything Kids' Knock Knock Book proves that laughter really is the best medicine!