The Stepsister
by R. L. Stine
Emily wants to like her stepsister, but it hasnt been easy. As soon as Jessie moves in, she takes over Emilys room, steals Emilys clothes, and lies to everyone. Then Emily picks up Jessie' diary and learns a horrifying secret. Is Jessie really capable of murder? Emily tries to tell her parents, but no one believes her. So its up to Emily to expose the real Jessieif she can stay alive.