As Kate Middleton and Prince William anxiously await the birth of their first child, the Duchess' family is already in a celebratory state of mind. On Thursday, July 11, Michael, Carole, Pippa, and James Middleton joined members of the royal family in the royal box at the Coronation Festival Concert at Buckingham Palace.

Aunt-to-be Pippa, 29, looked radiant in a demure floral frock with white lace overlay on the bodice, which she paired with a simple white clutch. Her brunette hair fell around her shoulders in loose waves, and she kept her makeup fresh and natural.

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James, meanwhile -- at 26, the youngest of the brood -- was dapper in a dark blue suit, crisp white shirt, and red tie. He stuck close to his sister as they milled about the box, along with their parents, Michael and Carole.

Organized by the Royal Warrant Holders Association, the Coronation Festival celebrates the 60th anniversary of Queen Elizabeth II's coronation. More than 200 royal suppliers, including Bentley Motors and Moet & Chandon, have set up pavilions and marquees on the grounds of Buckingham Palace for a four-day event displaying British "innovation, excellence and industry."

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Also in attendance at the Festival Concert was Prince Charles' wife, Camilla, Duchess of Cornwall, who happily spoke with reporters about the impending birth of her stepson's baby. "We are very excited, immensely looking forward to it, and waiting for the phone call," she shared.

Indeed, many people have been swept up in royal baby mania in recent weeks. Photographers and other members of the media started setting up camp outside St. Mary's Hospital a full 11 days before the Duchess' anticipated due date, and plans to commemorate the future heir's arrival have been announced by companies and countries all over the world.

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The Royal Mint, for example, said last week that babies born in the U.K. on the same day as Middleton's bundle of joy would be eligible to receive one of 2,013 free lucky silver pennies. And a supermarket near the royal couple's home in Anglesey, Wales, has reserved a parking space especially for them.

Of course, no one is more eager to meet the little boy or girl than the Duke and Duchess themselves. "Catherine and William are very much looking forward to the arrival of their son or daughter," a palace aide told Us."It's a very exciting time for the couple and their families."

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This article originally appeared on Kate Middleton's Family Attends Coronation Festival Concert Amid Royal Baby Mania: Picture