Fascinating new details about Grace Kelly’s life as the Princess of Monaco have been revealed.

In his new book, Life Photographing Royalty And The Famous, famed photographer Reginald Davis candidly revealed Grace was the “most difficult royal” he’d ever encountered during his four decades of work.

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“She only agreed to a private audience because I had previously had a private audience with [Queen Elizabeth],” he wrote — according to the Daily Express — of once photographing the actress with her husband and their three children sitting around the family’s baby grand piano.

grace kelly family getty images

Grace photographed with her family in 1967. (Photo Credit: Getty Images)

“When I asked her to play piano she claimed she couldn’t play a note,” he continued. And then of course she lifts the lid and plays like a concert pianist. I mean, really,” Davis wrote.

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“Everyone wanted to shoot Grace — she was such an attractive woman, why be so haughty, arrogant, and awkward? Of course, you’d never know that from looking at her face [in the photo] she seems every inch the relaxed, happy mother,” he said.

Davis confessed his favorite royal to work with was Queen Elizabeth’s younger sister, Princess Margaret. “She was just so vibrant — and had these beautiful azure eyes,” he wrote. “She really was the [Princess Diana] of her day. Everything I took of her was in demand.”

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He also loved photographing actress Sophia Loren. “She was just superb — so vibrant and vivacious and natural, and she treated you as if you had been her friend for years,” Davis said.

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