The Duke and Duchess of Cambridge were spotted exchanging a sweet glance at one another during Ellie Goulding's moving performance of Have Yourself A Merry Little Christmas.
The touching moment came as Kate hosted her Christmas concert at Westminster Abbey earlier this month. And it just so happens that Ellie performed at Prince William and Kate's wedding reception, so no doubt it brought back lots of happy memories for the royal couple, who tied the knot at the Abbey ten years ago.
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WATCH: William and Kate exchange loving look at Christmas concert
The special service, which will be televised by ITV on Christmas Eve, will pay tribute to the incredible work of individuals and organisations across the UK who have supported their communities through the COVID-19 pandemic.
The Countess of Wessex, Princess Beatrice and Edoardo Mapelli Mozzi, Mike and Zara Tindall, and Princess Eugenie, were all in attendance at the festive event.
The Duchess' family, including her parents Carole and Michael Middleton, and her siblings, also turned up to show their support.
The event features carols sung by the Westminster Abbey choir alongside Ellie and Leona Lewis. The service also includes readings delivered by the Duke of Cambridge, British Paralympian and junior doctor Kim Daybell and Good Morning Britain's Kate Garraway.
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Kate will pay tribute to those who have supported their communities during the pandemic
A first teaser clip released by ITV on Friday showed Kate wearing a festive-inspired Miu Miu cardigan.
"I'm so excited to be hosting Together At Christmas here at Westminster Abbey," the Duchess said to the camera.
The Cambridges usually spend Christmas with the Queen at her Sandringham estate, but Buckingham Palace is yet to confirm the royal family's plans.
Her Majesty has cancelled her pre-Christmas family lunch amid rising COVID-19 cases.
Royal Carols: Together At Christmas will air on Christmas Eve at 7:30pm on ITV and ITV Hub
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