The special reason why Kate Middleton invited her friends to Sandringham this week

The Duchess of Cambridge has cause for celebration this week

The Duke and Duchess of Cambridge joined the Queen in Sandringham for the morning service at St. Mary Magdalene church on Sunday, but the couple were not alone. Prince William and Kate, both 37, were joined by the Duchess' parents Carole and Michael Middleton and a group of their closest friends.


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As the Duchess is set to turn 38 on Thursday, the Cambridges hosted some of their closest companions at their country home, Anmer Hall, in Norfolk, to kick off Kate's early birthday celebrations, as they do most years. 

READ: Kate Middleton takes style tips from Sophie Wessex as she attends church with Prince William

Thomas van Straubenzee and his fiancée Lucy Lanigan-O'Keeffe

Among the guests were Thomas van Straubenzee, one of Princess Charlotte's godparents, and his fiancée Lucy Lanigan-O'Keeffe, who teaches at Thomas's Battersea – the school attended by Prince George and his sister.

Lady Laura Meade (pictured with Kate above), one of Prince Louis' godparents, attended with her husband James Meade, as well as Rose Hanbury, the Marchioness of Cholmondeley and her husband, David, the Marquess of Cholmondeley.

MORE: Prince William and Kate Middleton send rare personal message during emotional time

Rose Hanbury, wearing a brown hat, and her husband David attended

William and Kate's friends are said to have enjoyed traditional country pursuits over the weekend, before the royals returned to London to resume their duties. The couple also spent Christmas in Sandringham, where Prince George and Princess Charlotte made their public debut at the annual church service.

On Kate's birthday last year, William attended an engagement at the Royal London Hospital to mark the 30th anniversary of London's Air Ambulance Charity. The Duke was presented with a handmade card from a group of children, prompting the father-of-three to say: "Well done you for remembering, that's very impressive." He added: "I did remember this morning, so I was ok." A member of staff then asked, "Are you doing anything special today?" leaving a coy William to reply, "That would be telling!" before they all burst into laughter.

Over the festive period, Kensington Palace released a new photo of William, George, Charlotte and Louis, taken by Kate, to wish their social media followers a Happy Christmas.

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