The Case of the Missing Mother is a storybook in which The Muppet Show cast and crew are preparing a special Mother's Day show at The Muppet Theatre. Animal is depressed and distracted, however, upon learning that his mother has moved and he's lost her new address. Kermit and the others help Animal locate his mom, and mother and son perform a drum duet. The book was also released several times as a book and record or book and tape set. The version accompanying the record/tape featured altered dialogue and other minor text changes to match the audio adaptation.