Kaitlyn Small is the daughter of Henry Small and Jennifer Small, she has two older siblings, a brother Tyler Small and a half-sister Lana Lang, she attends a Metropolis boarding school with her brother Tyler. It was implied by her mother Jennifer, that her father Henry doesn't really pay attention to her, or her brother Tyler. Jennifer told Lana that Henry never committed to anything, not even their children ( Kaitlyn and her brother Tyler) and she felt it was unfair that he was attempting so hard to have a relationship with Lana. Kaitlyn's mother threatened to divorce Henry because he had been showing so much interest in his daughter Lana. Jennifer eventually decided to go through with the divorce. Kaitlyn presumably didn't get a chance to know her newly discovered sister.