Katherine Williams-Houwdegen is a Sim who lives in Veronaville. She is the younger niece of Simon Fischer. Katherine is the wife of Tybalt Capp (now Tybalt Williams-Houwdegen) and the mother of Caliban Williams-Houwdegen. She also got a child with Romeo Monty, Olivia.
Katherine appeared to be the younger cousin of Simon Fischer. She's suffering under the relation problems of her parents. They divorced because they both had an affair with someone. Katherine's mother, Carmen, gained the custody over her and her father was banned to see her ever again. Katherine had never forgiven her mother and she lost contact with her after she moved abroad for college.