Parties! The style, stars and scoop from Hollywood's hottest events

"I'm so honored," said Rachel Bilson of taking on the role of co-chair at the annual Whitney Contemporaries' Art Party and Auction, held at Skylight Studios in New York City. In addition to professing her appreciation for art at the event, presented by Max Azria, Bilson also showed off her flawless fashion sense in an Herve Leger bandage dress. Is her sense of style rubbing off on 7-year-old sister Hattie? "Yes! She borrows my clothes," Bilson sighed. "And I can't believe it, but soon her feet are going to be big enough that she'll be able to borrow my shoes!"