You'll never guess Princess Charlotte's adorable nickname from dad Prince William

Royal watchers rarely get a peek behind the scenes of Prince William and Duchess Kate’s family life. But something sweet was revealed when the couple took Prince George, Princess Charlotte and Prince Louis to visit Kate’s Chelsea Flower Show garden this past weekend: William has the most adorable nickname for his little girl.

Kensington Palace shared some heartwarming clips of the family interacting in the beautiful garden, which boasts a rope swing and even has a running stream! While the children played together (and Louis showed off his great walking skills!), William called over his daughter. But he didn’t call her Charlotte! Instead, he used the nickname “Mignonette” (see it at 0:15 in the clip below!).

The adorable moniker comes from the French word “mignon,” which means “cute.” It’s the perfect nickname for the sweet four-year-old, who showed off her vibrant personality in the clip and photos taken during their outdoorsy visit. Charlotte was spotted swinging on a rope swing in one snap. In another, she sits beside big brother George as they dangle their feet in the water.

The little princess isn’t the only royal with a nickname! Her older brother has one, too, and it was given to him by his peers at Thomas’s Battersea school in South London. In April, it was revealed to AOL that his pals have dubbed him “P.G.”—which, of course, stands for Prince George.

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