The Duchess of Cambridge in Jenny Packham

DAZZLING DUCHESS: The Duke and Duchess of Cambridge joined the royal family for the diplomatic corps annual reception held at Buckingham Palace Thursday night.

Queen Elizabeth, the Duke of Edinburgh, Prince Charles and the Duchess of Cornwall entertained more than 1,000 guests at the white-tie event. The yearly gathering honored members of the diplomatic corps, an assembly of foreign diplomats and representatives.

Kate Middleton wore a long, red Jenny Packham bespoke gown, its bodice covered with sequin embellishments. Known for shopping her closet, she had worn the dress last year for the Chinese state banquet to welcome the country’s President Xi Jinping and his wife Peng Liyuan. Also, held in Buckingham Palace’s ballroom, that was the first state banquet for the duchess and included more than 170 guests.

She topped off her look with a tiara that was one of Princess Diana’s favorites, the Cambridge Lover’s Knot tiara, which the Queen had given to the Duchess of Cambridge as a wedding present.

Made with 19 diamond arches and pearl pendants, the tiara was originally designed by E. Wollf & Co. for Garrard, and first belonged to Queen Mary. Other royals who have worn the royal heirloom include Queen Elizabeth and Princess Augusta of Cambridge. Prior to the dinner, the duchess wore a diamond crown to a diplomatic reception in 2013 and then sported a Cartier Halo tiara to her wedding in 2011.

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Last month, she joined the Duke of Cambridge, the Prince of Wales and the Duchess of Cornwall at a private memorial service for the Duke of Westminster, held at Chester Cathedral. The royals were among 2,000 guests to pay tribute to Major General Gerald Cavendish Grosvenor, a close friend of the royal family, who died from a heart attack on Aug. 9.

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