In her understated way, Queen Elizabeth spoke of how she never aspired to become Britain’s longest-reigning monarch – an achievement that is rooted in the solemn fact that she became a young queen at the premature death of her father, King George VI.
Charles was not with his 89-year-old mother on her milestone day, and instead spent it quietly working behind closed doors on a special project at Dumfries House, the home he helped save in southern Scotland. Nor did he say anything publicly, although his office highlighted his fond 2012 speech for his mother.
Although he remained silent, those who know Charles say he is proud of his mother’s landmark. “He will be full of admiration,” his former spokeswoman Colleen Harris tells PEOPLE. “She took over the role at such a young age, and has really shaped it in a way that the public have grown to love and admire – and that’s a great achievement.”
She adds, “In a way, the royal family is about stability and consistency, and she embodies that. You forget she’s aging until you say she’s been doing her job for more than 63 years.”
Of course, Charles won’t have forgotten – he has been immediate heir for as long.
An in-depth TIME profile in 2013 found a man not “itching to ascend the throne,” as is sometimes claimed, but one nonetheless who is impatient to achieve more in public life.
He has been carrying out a greater number of ceremonial duties on behalf of his aging mother in recent years.
At the same time, he has forged an identity built around his ongoing conservation efforts and successful projects like the Prince’s Trust to help disadvantaged youth find work and fund businesses, which is set to mark its 40th anniversary next year. In May, he impressed many with his statesman-like skills during a historic meeting with Irish Republican leader Gerry Adams. That path sets him apart from other heirs of the past.
“Charles is the first Prince of Wales who has actually done anything,” says former palace staffer Dickie Arbiter, who wrote last year’s On Duty With The Queen. “If you go back in history and the likes of George IV, all he did was date women, buy paintings and spend a lot of money. Edward VII and Edward VIII were the same. They were just playboys.
“This Prince of Wales has really put his money where his mouth is and done things for the community through the Prince’s Trust and other organizations,” says Arbiter. “People don’t always agree with what he says, but he has provoked debate and he has done something.”
When he does ascend, his wife of 10 years, Camilla, Duchess of Cornwall, will step into an even more high-profile role. Recent polls reveal there is a slightly growing acceptance among Britons for her being called Queen. Officially, Charles’s office has said she will be titled Princess Consort.
“It is a fact of life that she is married to the heir to the throne,” says Arbiter, “and when he becomes King she will become Queen.”
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