Kate shines in fashionably festive Vanessa Seward dress

The Duchess of Cambridge was fashionably festive on Monday (Dec. 19) as she attended a Christmas party in London wearing a pretty red and green Vanessa Seward dress. Kate was joined by her husband Prince William and brother-in-law Prince Harry.

The 34-year-old looked stunning in the floral print silk-jacquard woven knee-length dress from French fashion designer Vanessa Seward. She paired the elegant number, which is currently on sale for USD$623 on Net-a-Porter, with a black belt, clutch bag and pumps.

TAP TO VIEW GALLERYA photograph of Kate Middleton in a red and green Vanessa Seward dressKate looked festive in a red and green Vanessa Seward dress

With her hair worn down in her signature glossy blow dry and smoky eye makeup, it was the perfect party-ready outfit for Kate and a far cry from the casual sweater and jeans we last saw her in as she visited a Cub Scout Pack in Kings Lynn on Wednesday.

The royal trio were guests of honour at the Heads Together Christmas party, which was held to celebrate the hard work that volunteers give throughout the year. Princes William and Harry each joined a group breakout session where counsellors and volunteers shared knowledge and training on dealing with a range of issues, including homelessness.

Meanwhile Kate, 34, joined a live online chat about counselling with volunteers and young people from around the UK.

A photograph of Kate Middleton in a red and green Vanessa Seward dressThe Duchess was attending the Heads Together Christmas party

The party was hosted by youth support service The Mix, one of the eight charities involved in the royals' mental health campaign, Heads Together. William, Kate and Harry had the opportunity to speak to volunteers from The Mix, and heard about their personal experience of online and telephone counselling support.

At the Christmas party reception, the royals also kicked off The Mix Annual Awards by presenting the Volunteer of the Year Award.

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