- In "The Allergy Problem", Peg worries that she is allergic to Cat. This makes Cat sing a blues song about how they can't be best friends anymore. Thankfully, it turns out that Peg is only allergic to clovers.
- In "The Three Friends Problem", after Big Dog completes the games, Cat looks gloomy. His ears are drooping and at one point he seems to be crying a Single Tear. He also doesn't sing the "Problem Solved" song properly and he's very quiet. Peg is understandably confused and she, Ramon and the Neighbor Ladies try to cheer him up with exercises and a story, but they don't work. It turns out that he thinks Big Dog is her best friend instead of him. Fortunately, Peg reassures him that they're still best friends.
Tear Jerker / Peg + Cat