Rachel Bilson spent her weekend in Hawaii, where she hit the beach yesterday in a range of different bikinis. She and her younger sisters, Rosemary and Hattie, played on the sand, and they also put on snorkeling gear to explore under the water. Rachel's off enjoying a vacation with her family after the news broke recently that her engagement to Hayden Christensen is officially over. Newly single Hayden is throwing himself back onto the social scene, while Rachel's been staying more low key. She plans to keep busy, though, by continuing to explore her interest in fashion.