Cam, her best friend Eric, and Eric's mom are spending the day with
Eric's grandparents. But Grandpa and Grandma seem too tired to visit.
Every so often, a knock at the door wakes them up. But when they go to
answer, no one is there. Is a Knock, Knock Ghost on the loose? It's up
to Cam to solve the mystery!
Garden State Children's Book Award 2017 Nominee.