The royal family reportedly had a shocking reason why they approved Princess Diana for Prince Charles.

The Prince and Princess of Wales had a fairytale wedding. However, they had an unhappy marriage because Prince Charles was reportedly in love with Camilla Parker Bowles the whole time.

In an interview with Princess Diana in 1980, the princess admitted that she thought she was suitable for the future king due to her low number of notches on her bedpost.

Princess Diana told journalist Danae Brook that the royal family only accepted her for this shocking reason – she was a virgin. Also, her sister Sarah used to go out with the heir apparent, but the family didn’t accept her.

“You see my sister Sarah was going out with Charles last year and she talked about it to the press but she talked too much and they murdered her,” Princess Diana said.

“I’m OK because I haven't got a background. That's what everyone else seems to have. I mean I haven't had a chance to have that kind of background, I'm still only 19!”

Many believed that the royal family disapproved of Camilla for the same reason. Royal experts agreed that Camilla is the love of Prince Charles’ life, but he didn’t marry her because his family wasn’t supportive of their romance due to Camilla’s “experience.”

In the documentary “The Royal House of Windsor,” Dr. Piers Brendan clarified Camilla’s “experience” and how it affected the royal family’s view of her.

“It was absolutely vital to have on the throne somebody who was a virgin,” he said. “A future Queen must have no past.”

According to Penny Junor, Camilla’s past was an obstacle for her relationship with Prince Charles. She added that there was no suggestion that the Duchess of Cornwall was a loose woman, but she had boyfriends before the Prince of Wales.

Despite Camilla’s past, Prince Charles has always been in love with her and his feeling for Princess Diana couldn’t be compared to what he always feels for Camilla. In fact, Prince Charles wanted Camilla to be queen. However, he didn’t want to reign with Princess Diana as his queen.

Princess Diana and Prince Charles
Princess Diana and Prince Charles at the Chelsea Flower Show, London, May 1984. She is wearing a navy maternity coat by Jan van Velden. Getty Images/Jayne Fincher