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For her daughter Pippa Middleton's wedding, Carole Middleton wears a pale pink Catherine Walker coat dress.
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For her first solo overseas trip, Kate wore an icy blue Catherine Walker suit in the Netherlands.
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During a visit to Australia early on in her marriage to Prince Charles, she wore a light pink outfit, complete with a matching fascinator. "My wife and I spent a great deal of time researching what she wore for official visits abroad, even visiting countries in advance to make sure we had it right,” Said Cyrus, Walker’s widow, tells PEOPLE. “We tried to ensure that our designs bridged her ambassadorial role for her own country and also paid respect to each destination."
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For the 2016 Chelsea Flower Show in London, Kate blended in a bright green belted dress from the designer.
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During the same Australian tour, Diana opted for a soft pink gown, covered in a circular pattern and a ruffle — which goes perfectly with the bouquet of flowers she was given.
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For her grandson Prince George’s christening, royal mother-in-law Carole Middleton wore a navy blue Catherine Walker coat with lace details.
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For her arrival in Paris, the city where Princess Diana died in a tragic car accident 20 years ago, Kate wore a dark green Catherine Walker coat with a black collar and cuffs.
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The late princess's famed "Elvis Dress" was also a Walker creation. She wore it while presenting the British designer of the year award at the British Fashion Awards in London — a prize that didn't go to Walker. The next day, Diana sent Walker a note that said: "To my designer of the year."
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For Easter services at St. George's Chapel in Windsor, Kate channeled another legendary fashion icon — Jackie Kennedy — in a cream-colored coat and hat set from Catherine Walker.
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At the premiere of Who Framed Roger Rabbit?, Diana wore a dress that's currently on display at Kensington Palace in the exhibition, "Diana: A Fashion Story." Of the brand's relationship with Diana, Cyrus tells PEOPLE: "The relationship between the House and Diana was positive and professional. We saw our job as giving her the tools of her trade. She was always very polite, very courteous and very appreciative. She was never late for an appointment and whenever she wore a dress that was admired she’d thank us."
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Lady in red! Diana wore a red-and-black suit and matching hat to a visit to The Royal School for the Blind in Liverpool.
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Diana shined in a midnight blue gown — paired with the Queen Mother's sapphire brooch, which she fashioned into a pearl choker — at the CFDA Awards in New York City.
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