Something wicked

"Harper is dealing with too many new changes in her house. Her cousin, Leo, is now living with them; her sister, Kelly, has started working at a local makeup store, Jeune; and Harper's spirit hunter abilities have grown increasingly more powerful and uncontrollable, making her a target for possession. But when Harper and Dayo uncover a dangerous plot to steal youth from millions of innocent people, Harper must use all her powers to destroy an ancient evil and save her sister"--Publisher.