History
Yvonne Chilton was Astrid Bloom's half-sister, and at her birth the mother of both gave all of her maternal love to Yvonne at Astrid's expense.[1] It was later revealed that Astrid was not hunted by her parents, but she mentally controlled her 5 year old sister Yvonne to kill her parents in her sleep, and Yvonne was permanently interned.[2]