In a brief segment from the first season of Sesame Street (First: Episode 0005), an old lady carrying a sack of sea shells happens by Gordon, asking if the brick wall they're at is the way to the seashore. When she states she is selling sea shells at the seashore, Gordon assumes that she is Sister Susie. However, the old lady tells Gordon that her name is actually Penelope Pepperpot, to his bemusement.
Though seemingly unassuming at first, Penelope gradually displays signs of a quick temper, such as defensively asking "Yeah, what's it to ya?" when Gordon restates her previous statement that she is going to sell sea shells at the seashore, and calling him "smart guy" when he attempts to guess her name, to which she corrects him with a "Ding-dong, you're wrong!" (a phrase later adopted by another Caroll Spinney character, Oscar the Grouch).