Foster Cullens

Isabella Swan is a foster kid who has been bouncing around many foster homes since she was a little kid. She is now staying with the Cullens, and they seem to be nice, but she is developing feelings for another Cullen kid- Edwars, who already has a partner- Tanya. What will she do whenDerek, Tanya's true mate finds Tanya, but seeing Tanya is with Edward, takes Bella instead?