The "We're Growing" song from "The Big Dog Problem" is wonderfully sweet and heartwarming.
Peg's Mom: It seems like only yesterday you used to creep and crawl. You couldn't walk, you couldn't talk, couldn't do much at all. Then you grew a little bigger and turned into a tot. You made a sound and soon I found, you liked to talk a lot...
In "The Allergy Problem," Peg is determined to keep Cat as her best friend even if she turns out to be allergic to him. Thankfully, she's only allergic to four-leaf clovers.
When Peg tells Cat that her feelings for Big Dog can't be compared to her feelings for him and that he'll always be totally special to her.
The theme song is adorable, especially towards the end. "We are two, na na na na na/Me + You, na na na na na..."
The song sung at the end of "The Three Friends Problem", about how love (platonic love in their case) cannot be measured on a graph. They all sing the chorus, and Peg and Cat and the Neighbor Ladies are seen singing to each other.
Pretty much the entire Whole Episode Flashback showing how Peg and Cat met. They're somehow even cuter than their normal counterparts, especially the first time Peg hugs Cat and they come up with their little theme-tune! We also see the Neighbor Ladies become best friends at first sight, that the Teens (then Tweens) were already best friends, and the first time of many that Ramone came to Peg's aid!
In "The Roxanne Problem", when Roxanne finds out that Cat isn't really famous and math-savvy and that he and Peg have been lip-synching, she's not mad at either of them and admits to liking Cat.
