Jessabelle Gayle Swan is Isabella Marie Swan's fraternal twin sister. Jessabelle is not Bella's real sister though, she is the daughter of Klaus Mikaelaon and the god daughter of Carlisle Cullen. Carlisle, Esme, Rosalie, and Emmett are the only Cullens that like Jessabelle. Bella makes Jessabelle come with her and Alice to save Edward. What happens when Jessabelle and Caius meet for the first time?