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Duchess Kate's due date has arrived and the royal family is anxiously awaiting to hear that she's in labor -- but they aren't exactly sitting by the phone! Queen Elizabeth II, Prince Charles and Camilla, Duchess of Cornwall attended the Coronation Festival, which celebrates the 60th anniversary of the Queen's Coronation, on the grounds of Buckingham Palace in London on Thursday.

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Prince Charles' wife, Camilla, 65, happily spoke with reporters about the impending arrival of stepson Prince William and his wife, Duchess Kate's first child. "We are very excited, immensely looking forward to it and waiting for the phone call," she shared.

The duchess, 31, is excited to become the mother of England's future King or Queen as well. A family source told Us Weekly last week that she is "feeling great" and "full of energy." But Prince William's wife does have a few jitters. "Naturally she is a little nervous about the big day, what new mum wouldn't be?" the source explained.

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When the royal baby arrives, a St. James Palace rep told Us Weekly a framed announcement will be placed on a wood and gold easel just behind the gates of Buckingham Palace shortly after the birth. The announcement will include the baby's gender, weight and time of birth, but the name will be revealed at a later date.

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"Although an electronic release will go out, we want there to be a degree of theatre about the birth announcement," a Palace rep told Us. "This is the birth of the third in line to the throne so it is very important. It is an extremely important occasion."


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