When Prince Charles becomes King, his subjects will bow to him, but that doesn’t stop him from getting down on his own knees to play with his grandchildren. “[Charles] will crawl about with them for hours, making funny noises and laughing,” said his wife, Camilla Parker Bowles, in the BBC documentary, Prince, Son and Heir: Charles at 70. “My grandchildren adore him.”

At 70, the Prince of Wales has found joy in his family and purpose in his work. “He is his own man, passionate and creative,” Queen Elizabeth said at his Nov. 14 milestone birthday party. Camilla also attested to her husband’s big heart. “I don’t think people realize quite how kind he is,” she said in the documentary.

Prince Charles and Camilla Parker Bowles
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The oldest son of Queen Elizabeth and Prince Philip grew up in a household steeped in royal protocol. “Children were seen and not heard,” an insider exclusively told Closer Weekly in the magazine’s latest issue, on newsstands now. With a tough disciplinarian for a father and a mother busy with royal duties, Charles learned to rely on himself. “Opening up doesn’t come naturally to him,” an insider shared.

This stoicism caused problems during his first marriage to Princess Diana, who overshadowed him in popularity. Their scandalous divorce put Charles on the defensive in public and at home. “Prince Harry was always a mommy’s boy,” said the first insider. “He never developed a strong bond with Charles.”

Diana’s 1997 death helped Charles become more sensitive to his sons’ needs. “If he could turn back time, he would’ve done things differently,” another insider said. In recent years, Charles counseled son Prince William and his wife, Kate Middleton, on handling the spotlight and stepped in with tough love when it looked like then-teenage Harry’s partying was out of control.

Prince Charles, Prince Harry and Prince William
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This investment helped strengthen their relationships. “He’s our father, so of course he’s gonna be there for us,” Harry said in the documentary of Charles, who escorted his bride, Meghan Markle, down the aisle last May. “I was very grateful,” admitted Harry of the special moment.

William, meanwhile, takes delight in Charles’ bond with Prince George, 5, Princess Charlotte, 3, and Prince Louis, 7 months. “He’s brilliant [with them],” said William in the film. “I would like him to have more time with the children.”

But Charles has no intention of slowing down. He raises more than $125 million for charity each year and the line of organic confections he founded, Duchy Originals, has become a global success. “The man never stops,” said Harry. “He will fall asleep on his notes [and] wake up with a piece of paper stuck to his face.”

Prince Charles 70th Birthday Prince Louis
Chris Jackson/Getty Images for Clarence House

Everything may change after he ascends to the throne, but right now Charles is happy to have time for his passions. “He’s a man who lives in the present,” royals expert and TV producer Nick Bullen told FOX News. “He just wants to do the job really, really well. When he becomes king, he’ll do that job really, really well, too.”

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