Actress Rachel Bilson is designing her own maid of honour dress for THE O.C. creator Josh Schwartz’s upcoming wedding to her best friend.

Bilson, who last week announced she’s launching her own line with fashion brand DKNY, has been working with designer Brian Reyes on the gown.

The 26-year-old, best known for her role as Summer Roberts on TV hit The O.C., will be a maid of honour at the event.

Bilson says, "I introduced them and now they are getting married. It’s so exciting. I’m pretty proud of this one."