Immune (Twilight fan-fic) The Story of Bella's Sister

8 years ago, Kira swan was diagnosed with a very rare disease, no one could figure what it was, so they named it the X-syndrome, what makes it so rare? Kira is the only who has had it. Kira lives as a normal girl in Forks, Washington with her dad Charlie, well almost normal but when her twin sister Bella moves from F...