Even overcast skies couldn’t dampen the high spirits of the young royals. At the August 9 King’s Cup royal sailing regatta, Prince George, 6, toured the yachts with glee, while his sister, Princess Charlotte, 4, cheekily stuck her tongue out at her maternal grandfather, Michael Middleton, over the crowd. “Her mother, Kate [Middleton], thought it was hilarious,” confides a royals insider.

As the long, sweet summer days rush to a close, Prince William and Kate’s kids — including Prince Louis, 15 months — have been reveling in their freedom. “They’re embracing family time,” says the insider. “They love being outdoors and running around freely.”

This month, Queen Elizabeth II, 93, will host the young parents and their kids at Balmoral Castle, her beloved 50,000-acre Scottish country estate. “I think Granny is the most happy there,” William’s cousin Princess Eugenie says, confiding that vacations to Balmoral include “walks, picnics, dogs — a lot of dogs! You just have room to breathe and run.”

Kate Middleton with Prince George and Princess Charlotte
ANDY RAIN/EPA-EFE/Shutterstock

The children are already excited. “George received a pair of binoculars for his birthday and can’t wait to use them,” says the insider. “And the queen has promised to go riding with Charlotte.” Like everyone, the monarch has noted how much Charlotte takes after her. “They have a very strong bond, although she adores all of her great-grandkids,” notes the insider.

This summer has been especially meaningful for William and Kate, both 37. “While he is actually the stricter parent, both of them want to let their kids be kids,” says the insider. “They’re happy to have this down-time together.”

Ahead of their sailing fun, an eyewitness exclusively opened up to Closer Weekly about seeing Kate, George and Charlotte on a shopping trip. While you might think the royal family would skip the lines, turns out “they queued at the checkout like a normal family.”

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