Had a similar but a little scarier experience with a curious 3~4 year old (friend's son, while visiting my place). Instead of a Cheeze Sandwitch, he put his hand inside the load slot. That triggered the entire load sequence, including trapping his hand as the carrier moved down towards the playback head.
LOUD screaming, I wasn't sure what to do, killing power didn't change anything, so I just grabbed his wrist and pulled. His hand came out, there was a lot of "there, there" from mom, but no real damage done.