Zac Posen shares unseen photo of Princess Eugenie in her second wedding dress

Blushing birthday beauty! In honor of Princess Eugenie’s 29th birthday (March 23), American designer Zac Posen shared a gorgeous unseen photo of the British royal in her second wedding dress that he designed. “Every now and then you meet somebody who just knocks your socks off. This last year I got to know a young lady who possessed natural elegance, a heart of gold and sophisticated humor,” he captioned the photo.

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Every now and then you meet somebody who just knocks your socks off. This last year I got to know a young lady who possessed natural elegance, a heart of gold and sophisticated humor. My studio and I had the honor (and the best time) collaborating with her on her special gown. Best of all she is dedicated to using her privilege to help our world and its people with her project @the_anti_slavery_collective. Happy Birthday! @princesseugenie ✨

A post shared by Zac Posen (@zacposen) on Mar 24, 2019 at 9:55am PDT

Zac added, “My studio and I had the honor (and the best time) collaborating with her on her special gown. Best of all she is dedicated to using her privilege to help our world and its people with her project @the_anti_slavery_collective. Happy Birthday! @princesseugenie.”

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The image posted on Sunday, March 24, shows Zac holding the cape of Eugenie’s blush dress. Queen Elizabeth’s granddaughter changed into the ethereal gown for her wedding reception following her and Jack Brooksbank’s service at St. George’s Chapel at Windsor Castle back in October.

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A post shared by Princess Eugenie (@princesseugenie) on Mar 24, 2019 at 9:01am PDT

Zac was inspired by the beauty of Windsor and the White Rose of York, which was subtly embroidered on both the shoulder and back of the dress. Eugenie’s silk Zac Posen gown, as well as her Peter Pilotto dress worn for the wedding ceremony, are currently on display at Windsor Castle.

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Jack’s wife opened up about working with Zac for the exhibit’s audio guide. “I’ve had a lifelong admiration for him as a designer – and because Zac is based in New York and I lived there for some time when I was younger, and for me it was an easy decision to make and Zac is such a cool, fun, brilliant designer and friend,” Eugenie revealed. “I wanted something reminiscent of Grace Kelly in To Catch a Thief, so I showed that for reference and Zac came up with this silk that he had found from Manchester. Every single draping effect, every single detail, every button is all painstakingly done by him and his team.”