Duchess Kate Wore the Most Festive Dress to a Christmas Party, Naturally

There's our girl, right on theme! Duchess Kate — alongside Princes William and Harry — attended a Christmas party for The Mix youth organization in London on Monday, December 19, and of course she chose a festive dress for the occasion. See it in Red Carpet Daily, presented by DirecTV!

Catherine Duchess of Cambridge Prince William Prince Harry
Catherine, Duchess of Cambridge, and Prince William, Duke of Cambridge, with Prince Harry attend a Christmas party for volunteers at The Mix youth service on Dec. 19, 2016, in London. The Mix youth service works with Their Royal Highnesses' Heads Together campaign. Chris Jackson/Getty Images

The Duchess of Cambridge, 34, cozied up in a printed red and green Vanessa Seward dress, cinched at the waist with a gold-buckled belt. She accessorized with a square clutch, suede stiletto heels and embellished gold hoop earrings.

Vanessa Seward Cai Floral-Print Silk-Jacquard Dress

Best news? Kate's dress is on sale! While the Cai dress, which features a buttoned neckline and pockets, normally retails for $1,245, it's currently 50 percent off at net-a-porter.com, making it $623. (A steal, we know.)

The royal mom of two, her husband and Harry were on hand to meet with The Mix's mentors and volunteers, who help young people between the ages of 13 and 25 through many kinds of challenges, including breakups, mental health issues and addiction. The trio — who launched their mental-health-focused Heads Together campaign earlier this year — joined in making Christmas decorations and presented the Volunteer of the Year award.

"I think it's amazing what Their Royal Highnesses are doing for young people through the Heads Together campaign," Louisa, a volunteer who's autistic and who has used The Mix's support service since she was 14, tells Us. "Their openness has got everyone talking about mental health, and that's such a good thing. They're making young people feel braver and less alone, and we need that now more than ever."

For more on their charitable visit, watch the video! And keep watching to see Emma Stone's most glamorous looks from her La La Land tour — including the two sunny marigold dresses that made her red tresses pop.

(Wardrobe: Bailey 44)

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