Katelyn is one of the "Kaitlins" and a student at Waverly Hills Elementary School.
Katelyn has blonde hair held back by a lavender headband and wears a lavender shirt with a purple vest and a dark-purple skirt. She also wears a bracelet on her left wrist.
She and the other Kaitlins greet Lisa during lunch and try to ask her what her favorite song by Alaska Nebraska is. When they find out that Lisa doesn't know who Alaska is, they proclaim her as "lame" and abandon her. Later, she and the other Kaitlins find out about Bart's arrest by Chief Wiggum (which turned out to be a stunt in order for Bart to achieve popularity at the school) via gossip and believe him when he lies to them that Lisa is a friend of Alaska's. They immediately gossip the news all around the school, making Lisa popular. However, when Lisa tells her and the other Kaitlins that she isn't Alaska's friend, they become angry and pursue her around Waverly Hills, but apparently lose her. She hasn't been seen since.
- Like Sherri and Terri, the Kaitlins can also be identified by their placement in their lineup; Katelyn is always found at the left of the group.
- Her favorite Alaska Nebraska song is "Touch a Star".
- Her blonde hair and personality make her very similar to Alex Whitney.