The Duke of Cambridge and his oldest children were photographed on Sunday as part of a local sporting event. The photos, which were obtained by the Daily Mail, showed Prince William alongside Prince George, seven, and Princess Charlotte, six, at a Father's Day half marathon on the Sandringham Estate.
The royals appeared to be having lots of fun together as they gathered around a microphone to count down to the start of the race.
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George and Charlotte were dressed in shorts and trainers while their dad, who turns 39 on Monday, wore a blue shirt with matching navy chinos.
Run Sandringham is an event that aims to raise money for good causes while runners enjoy the scenic surroundings of the Queen's Norfolk estate.
WATCH: Prince William's never-before-seen photo with George, Charlotte and Louis
The Cambridges own a country home in Norfolk, Anmer Hall, which they visit during the children's school holidays or occasionally at weekends. During the school term, they are based in Kensington Palace in London as George, Charlotte and Louis attend school and nursery nearby.
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Earlier in the day, William appeared in another heart-warming image to mark the special occasion.
As part of a Father's Day video, Kensington Palace released a never-before-seen photo taken with his three children, including youngest child Prince Louis, three, which appeared to have been taken on the day of the 2019 Trooping the Colour ceremony.
The royal children attend school nearby
The doting dad and his kids were pictured on the steps of their home, Kensington Palace, with the future King looking smart in his military uniform.
George, Charlotte and Louis, meanwhile, all coordinated in blue.
An accompanying caption read: "Wishing fathers everywhere a happy Father's Day."
Fans quickly showed their appreciation for the sweet video, which also included throwback photos of Kate and her dad Michael Middleton on her 2011 wedding day, a group photo of the Queen and Prince Philip with their great-grandchildren, and another snap of Prince Charles with his young sons William and Harry in Scotland.
Many wished William a happy Father's Day in the comments section, and others noted how cute the Cambridge children are.
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