Prince George and Princess Charlotte Dressed Down for Father's Day with Prince William

While it's nothing new to see the royal family dressed to the nines, it's a special occasion when they go a little more casual, which is exactly what happened when Prince William, Prince George, and Princess Charlotte made an appearance at a half-marathon that took place at Sandringham estate. According to People, which published the photos, the royals helped count down the race at the starting line and cheered as the runners headed off on their runs.

Both George and Charlotte wore shorts for the occasion, something that their very proud pops rarely wears during public outings. George paired his navy shorts with a patterned button-down shirt and matching Nike sneakers. Charlotte wore a pink sweater and matching magenta sneakers with her hair in an Ariana Grande-approved half-ponytail. William wasn't as dressed down. He was in his usual uniform of a pale blue button-up, navy slacks, and suede boots. Kate Middleton and baby Prince Louis weren't at the event.

Photo by Comic Relief/BBC Children in Need/Comic Relief via Getty Images

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The race happened on Father's Day and Kate did post a tribute to her husband and future king of England on Instagram.

"Wishing fathers everywhere a happy Father's Day," she captioned the image, which showed a bulletin board with photos of Kate's father, Prince Philip, Prince Charles, and William.

The marathon appearance comes after a more serious event for William. Back on June 11, he joined Queen Elizabeth, Kate, Prince Charles, and Camilla, Duchess of Cornwall, to meet global leaders at the G-7 economic summit.