King Charles 'Works All Day Long' Until 4 A.M. Finding 'Brilliant Solutions'

Prior to King Charles ascending to the throne, he spent 64 years as the Prince of Wales and was fiercely dedicated to the region. Now that the monarch has become king, he's maintained his strong work ethic.

"That’s a really daft thing to say, but behind the camera, they’re really fun, clever, kind people," royal family member Sophie Winkleman said in an interview as she gushed over His Majesty and their bond.

Charles "is a very dear friend. I spend a bit of time with him," Sophie said. "You see how he works all day long, has a quick supper and then disappears until about 4 a.m. to write letters. He cares about so many things, and he comes up with brilliant solutions."

Charles' career was discussed in Prince Harry's memoir, Spare. During his time as the Prince of Wales, Charles expanded the role, increased the value of the duchies and built one of the U.K.'s most prominent brands.

“His own work was also a kind of religion because he was furiously trying to save the planet,” Harry wrote. “Countless times, late at night, Willy and I would find him as his desk amid mountains of bulging blue postbags — his correspondence."

“More than once we discovered him, face on the desk, fast asleep. We’d shake his shoulders and up he’d bob, a piece of paper stuck to his forehead," the Duke of Sussex recalled.

Charles spent over six decades in the position Prince William inherited, and according to an insider, the pair struggles with the power dynamic between them.

OK! previously reported His Majesty and the Prince of Wales' approach to their duties differs.

“Charles absolutely wants William to plow his own furrow, he is encouraged to do so, just as he was," an insider told an outlet.

“I am sure they will butt heads as Charles is allergic to anyone telling him what to do, and William is not exactly famed for his subtlety," the source continued. "But I think it is broadly seen as a productive rivalry, rather than a destructive one, because William respects his father’s ‘rank’ as head of The Firm."

Although William hopes to take on more responsibilities, he admires Charles and understands his place within the line of succession.

"Ultimately the monarchy is a hierarchical structure based on military principles, and when push comes to shove, you have to obey orders from your superiors," the pal stated. "That’s what William and Kate understand, and Harry and Meghan could never accept. They would not do as they were told.”

“William and Kate would do things like give you two weeks off if your father died, while Charles’ office has a more workaholic vibe," they added.

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Winkleman spoke to People.