The fashion world is in mourning as they come to terms with the tragic news that celebrated designer Kate Spade has passed away. The 55-year-old was the iconic visionary who founded the fashion brand Kate Spade and the New Yorker had some of the biggest names as her clients, including Kate Middleton and her younger sister, Pippa Middleton.

The siblings were among many high-profile names who've been spotted donning one of Kate's unforgettable creations — from dresses, bags, and earrings. While Kate sold the company back in 2006, the fashion house continued to foster their royal connection.

Their president, Deborah Lloyd, once told People, "The Duchess embodies all of the qualities of the Kate Spade New York girl — she is quick, curious, playful, and strong and she is an incredibly interesting woman, leading an incredibly interesting life. Being a Brit myself, this moment is particularly meaningful for me." Scroll down to see some of the best photos of Kate and Pippa wearing Kate's stunning designs.

Kate — November 2017

Kate was last spotted wearing a Kate Spade design in November 2017 when she visited The Foundling Museum in London. Within hours of the engagement, the dress sold out.

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Kate — April 2017

The Duchess dipped into her fun side last April. The mom-of-three attended the opening of the musical 42nd Street on the West End and she wowed in a red dress and a pair of ruby-red chandelier earrings by Kate Spade. The jewels sparkled against Kate's crimson Marchesa Notte tulle gown.

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Kate — October 2016

In October 2016, the Duchess dressed in Kate Spade again for World Mental Health Day. The stunning floral frock, which retails for $381, was an elegant pleated chiffon dress. It featured a pretty feminine rose print, with a neck tie — a signature look for Kate Spade. The outfit was completed with with nude heels, matching L.K. Bennett clutch, and her signature blow dry.

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Pippa — Through the years

Pippa is a Kate Spade girl through and through! The 34-year-old turned to the brand for one of her honeymoon frocks when she came to Australia last May. Over the years, Pippa's woven Kate Spade handbag has been on high rotation.

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This post was written by Chloe Lal. It originally appeared on our sister site, Now to Love.

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