"The Merry-Go-Round Broke Down" is a song most commonly associated with Looney Tunes. Roger Rabbit sings it to entertain barflies in Dolores' bar, and Eddie Valiant later sings it to make the Toon Patrol laugh themselves to death. These are not the actual lyrics to the song; they were written for the film only. Since pretty much all of the Looney Tunes are friends with both Roger and Eddie, it stands to reason that Roger and Eddie would be familiar with the song.