Territorial Cat

Cat gets your finger if you go into his space.

Child learns that cats are territorial . He/ she will be curious about what to put in the hole and the cat knows when to come out.
Child inserts finger into the hole, alarming the cat that will open the door and bite/claw the finger until the child removes it.
Most/all of the toy is made of plastic, so it shouldn’t be too durable. Perhaps a small button or even motion sensor can be placed in the hole to trigger the cat’s attack