Katie is a nine-year-old girl who loves to swim. She always wears a long-sleeved swimming shirt, long-sleeved swimming togs, a pair of swimming goggles, a pair of swimming gloves, a swimming cap and a pair of swimming shoes. She lives at a house with her parents and her four sisters, who love swimming just as much as her. She also attends a girls-only swimming school and she's made lots of friends there.