Sara Paxton will star in "Aquamarine," the story of two 12-year-olds who befriend a mermaid they find at their parents’ beach house, according to the Hollywood Reporter. The film, based on Alice Hoffman’s children’s book, will be directed by Elizabeth Allen, and will also star JoJo and Emma Roberts. Paxton also starred in "Sleepover" and has a recurring role in the WB show "Summerland."