"George is turning 9! 🎂🎈" the couple wrote on Instagram.
In the photo, Prince George can be seen smiling from ear to ear in a baby blue polo. As is tradition, the birthday portrait was taken by the Duchess of Cambridge earlier this month while on vacation in the U.K.
The young royal has had a busy recent couple of months leading up to his birthday.
Earlier this month, Prince George made his Wimbledon debut, attending the final day of the London tennis tournament with his parents. George looked dapper in a navy blue suit, white shirt and diagonally-striped navy blue, green and white tie.
Throughout the game, photos show the father-son duo chatting and bonding.
George also appeared in a sweet family photo alongside siblings Princess Charlotte, 7, and Prince Louis, 4, for Father’s Day in June. The three children grinned widely as they huddled affectionately around dad William for the family portrait, which appears to have been taken when the British royals visited Jordan last fall.
Along with the rest of the royal family, Prince George took part in Queen Elizabeth II’s Platinum Jubilee celebrations in June, including an appearance at the Platinum Pageant. George stole some of his grandmother’s thunder with his colorful facial expressions in the royal box.
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That same month, George joined his parents and siblings for a visit to Cardiff Castle in Wales, where George and little sister Charlotte were spotted carrying bouquets of flowers as they walked the streets.
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Contributing: Naledi Ushe
This article originally appeared on USA TODAY: Prince George turns 9: See new photo of Prince William and Kate's son