Prince William Reveals Kate Middleton's Adorably Basic But Stress-Relieving Hobby

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It seems the Duchess of Cambridge loves to color.

Prince William let that adorable tidbit slip while awarding the Order of the British Empire to adult coloring book illustrator Johanna Basford this week at Buckingham Palace.

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"Prince William actually said that his wife likes to color in The Secret Garden, which was really sweet," Basford told the Telegraph on Tuesday, referring to her first coloring book, which sold over 1 million copies and arguably started the adult coloring craze.

"I think we've just seen the coloring community flourish," Basford continued of fans like Middleton. "I think people are just craving a digital detox."

The best-selling author also hinted that Buckingham Palace -- and maybe the Duchess herself -- has inspired her next book. "I'm working on a new book just now and it's set in a castle, funnily enough, so I will definitely try to remember everything," she said. "I'm sure little snippets of today will feature in the book."

While it's no surprise that Middleton's into coloring -- she was an art history major at St. Andrews, and has chosen London's National Portrait Gallery and The Art Room, an art therapy charity for children with emotional and behavioral difficulties, as some of the royal causes close to her heart -- we do have one question about the Duchess' new hobby: does she color inside the lines?

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Though Middleton's new favorite activity is definitely something she can enjoy with her children, 3-year-old Prince George and 1-year-old Princess Charlotte, it seems the royal tots have interests of their own.

During a tea party at London's Natural History Museum last week, the Duchess revealed George's obsession with "dinosaurs and volcanoes."

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