Camilla Parker-Bowles is not threatened by Kate Middleton, according to a journalist.

In Tom Bower's book "Rebel Prince: The Power, Passion and Defiance of Prince Charles," he wrote that the Duchess of Cornwall is not bothered by Middleton winning the public's affection. Bower claimed that Camilla is apparently sure that she will be the first commoner queen.

"For her part, Camilla was unconcerned about Kate taking the limelight," Bower wrote. "Camilla also dismissed the presumption that Kate would be the first commoner Queen. 'That'll be me,' she'd say with a laugh."

However, unlike Camilla, the Prince of Wales was reportedly "threatened" by the Duke and Duchess of Cambridge's popularity. Prince Charles is apparently bothered by the possibility that his son and Middleton will overshadow him as more British people prefer them to take over the throne after Queen Elizabeth II.

"Charles saw Kate and William as the new stars and feared he'd be in trouble," Robert Higdon, the chief executive of Charles' charity foundation in America, told the investigative journalist.

According to a poll conducted by YouGov in November, 56 percent of Brits want Prince William to be the next king. Meanwhile, only 13 percent and 10 percent want Prince Charles and Prince Harry for the position, respectively.

On the other hand, 63 percent prefers Middleton to be the next queen. Only eight percent favors Camilla, while three percent wants Meghan Markle.

However, although the poll is interesting, it does not determine who will be the next king and queen. Based on the line of succession, Prince Charles, the monarch's eldest son, will still be the one to take over the throne after Her Majesty.

In addition, Prince William is not in a hurry to be the next ruler. In fact, the duke has no plans to compete with his father even if this means that his regime will be more brief.

"Although like his father, William will be destined to have a far shorter reign than his grandmother, he has said he has no desire to 'climb the ladder of kingship' before his time," Gill Knappett, who wrote "Charles, Prince of Wales," told Express.

Knappett is positive that Prince Charles will win the hearts and minds of the people when he takes over the throne. "Without doubt, when the time comes our new King will serve with a strength of character that will continue to see our Royal Family the envy of the world. When that will be is for God alone to know," the author said.