Prince William revealed his adorable nickname for his 4-year-old daughter Charlotte as the family visited the Chelsea Flower Show over the weekend.

William could be seen playing on a swing with George, 5, and Charlotte in a clip posted by Kensington Palace.

After getting his son to give the swing a mark out of 10, the Duke of Cambridge then called over to his daughter.

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However, fans noticed that instead of calling her by her name Charlotte, he instead referred to her as “Mignonette,” which is the French word for cute.

The royal family are certainly no stranger to nicknames, with George being known as PG Tips and Georgie.

Kate also revealed the family called Charlotte “Lottie” during a royal engagement back in March.

The Duchess has a nickname as well; Squeak.

She previously said: “I was nicknamed Squeak just like my guinea pig. There was one called Pip and one called Squeak because my sister was called Pippa and I was Squeak.”

William and Kate are also parents to 13-month-old son Louis.

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