Dear 100 Hour Board,
In cartoon shows, do cartoons exist? Or are all shows in cartoon shows live action?
Dear Love Ducks,
Yes, cartoons exist within cartoons. In Phineas and Ferb they watch a lot of a cartoon called Pinhead Pierre, in addition to some other ones. In Board Question 83657, Frere and Tally give some other examples, as well.
In Steven Universe, there's a really strange cartoon called Crying Breakfast Friends!