Kate Middleton wore a special accessory to a performance of Dear Evan Hansen this week

Kate Middleton topped off her elegant look during her recent trip to the theater with a special item of jewelry.

The Duchess of Cambridge dazzled during her outing with husband Prince William on Tuesday in a pair of Queen Elizabeth‘s diamond chandelier earrings. Kate, 38, wore a black midi-length dress by Eponine paired with sparkling heels (and matching clutch, both by Jimmy Choo!) for the special occasion, while William, 37, dressed up in a blue suit and tie.

This isn’t first time Kate has borrowed the Queen’s jewelry; this particular pair of earrings is one of the royal’s favorites, and she’s worn them on multiple occasions.

The first time the royal mom of three wore the earrings was at a British Academy Film Awards dinner held in Los Angeles in 2011. Kate has worn them to a number of events since, including the 2017 Variety Performance and the 2018 Tusk Conservation Awards.

Catherine, Duchess of Cambridge,
Credit: Karwai Tang/WireImage
Catherine, Duchess of Cambridge,
Kate Middleton
| Credit: Karwai Tang/WireImage

The royal couple attended a special performance of the hit Broadway musical Dear Evan Hansen at the Noël Coward Theatre in London on Tuesday, held on behalf of The Royal Foundation.

In a note for the show’s program, William said, “Catherine and I are delighted to join you this evening for a special charity performance of Dear Evan Hansen at the Noel Coward Theatre.”

Catherine Duchess of Cambridge and Prince William
Kate Middleton and Prince William
| Credit: Tim Rooke/Shutterstock

“One of the issues that we care passionately about is mental health and we are pleased that Dear Evan Hansen is helping to start important conversations between parents and teenagers about this important subject. Through initiatives including Heads Together and Heads Up, the Royal Foundation is helping tackle the stigma and change the conversation around mental health,” he added. “We are particularly proud that Shout , a mental health support service launched by the Royal Foundation, is one of four not-for-profit partners of Dear Evan Hansen providing mental health resources to audiences of the show.”

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The award-winning musical tells the story of a boy named Evan who struggles social anxiety and strongly wishes to connect with his peers — so much so that he fabricates a friendship with a deceased student in order to be closer to the boy’s family.

The topic of mental health is a key priority for William and Kate’s foundation, which works to help encourage people to openly discuss their mental health as well as fight the stigma that comes along with it.