Nicole and Joel spark new engagement rumors

Nicole Richie got tongues wagging the other night when they showed up at the YSL Pool Party with Joel Madden on her arm and a giant diamond ring on her finger. "It was one big rock surrounded by more diamonds," a source said. Richie refused to talk about the ring, and Madden was "overly attentive to her - keeping his arm around her all night - and repeatedly asked her if she was okay."source