Nick Cassavetes has hired both Dakota and Elle Fanning to star opposite Cameron Diaz in his latest directorial effort My Sister's Keeper. According to Variety, the film is based on a novel by Jodi Picoult.

Elle will play a girl that sues for emancipation form her parents. Elle's chracter was conceived as a genetic match for her cancer-ridden sister with the hopes of saving her life. Diaz will be playing the mother of the two girls.

This marks the first time the two siblings will act in scenes for a film together. Both girls appeared in Sean Penn's I Am Sam. Jeremy Leven wrote the screenplay, which is set to go into production before the end of the year.