Prince William and wife Kate Middleton have released a new picture of their eldest son, Prince George, to mark his ninth birthday.

The picture shows the young royal, who celebrates his birthday on Friday, wearing a light blue collared shirt and giving a broad smile.

The photo was taken by the Duchess of Cambridge on a family holiday in Britain earlier in July. The Cambridges usually spend the British summer at their country residence on the Queen’s Sandringham estate.

Kate is a keen photographer and often takes the photos released to mark the birthdays of George and his younger siblings, Princess Charlotte, 7, and Prince Louis, 4.

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The three Cambridge children are gradually becoming more involved in royal events. Earlier this year, Prince Louis stole the show with his antics at celebrations to mark the Queen’s platinum jubilee.

All three children rode in a carriage during the Trooping the Colour, for the first time, and also appeared twice on the Buckingham Palace balcony.

George has also been recently seen out and about with his parents, and without his younger brother and sister.

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A fortnight ago, he joined William and Kate at the men’s final between Australia’s Nick Kyrgios and Novak Djokovic at Wimbledon. Afterwards, he met 2022 champion Djokovic behind the scenes, and even got his hands – briefly – on the Wimbledon trophy.

George’s ninth birthday comes ahead of a reported move for the family, and a change in schools. The Cambridges are said to be poised to move to a house on the Queen’s Windsor Castle estate, with all three children expected to start at a new school later in the year.

The move would also bring them closer to the duchess’s parents, Mike and Carole Middleton. They live in Buckleberry, about 40 minutes’ drive from Windsor.

Prince George is third in line to the throne, behind his father Prince William and grandfather Prince Charles.