Prince Philip apparently had some relationship advice for his first-born son Prince Charles during his marriage to Princess Diana. Similarly, Queen Elizabeth II is also said to have given advice to his “sobbing” wife.

As noted by E! Online, the Duke of Edinburgh gave the future king some words of “wisdom” after he came to him seeking counsel on wanting to be with another woman while still married. The other woman, of course, is his current wife, Camilla Parker Bowles.

The outlet noted last August that in 2017, a Channel 4 special in the UK revealed Princess Diana learned of Prince Philip’s advice to her former husband about Camila after years of being married. The quotes came from tapes of Diana’s private conversations with her voice coach.

“My father-in-law said to my husband, 'If your marriage doesn't work out, you can always go back to her after five years,'" the late Princess of Wales said. She added, "Which is exactly—I mean, for real I knew that it had happened after five—I knew something was happening before that but the fifth year I had confirmation."

When a “sobbing” Diana went to her mother-in-law, Queen Elizabeth II, for advice, she was reportedly told, “‘I don’t know what you should do. Charles is hopeless.’”

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According to the outlet, Charles met Camilla in 1971 and the two “rekindled” their affair in 1979 following a death in his family. During this time, Philip reportedly wrote his son a letter, shaming him for having "paraded" his girlfriends around. Charles went on to date Diana in July 1980 and the two wed the following year after Philip asked his son to propose or break off the relationship.

Following the birth of Diana and Charles’s sons, Prince William and Prince Harry, the Prince restarted his romance with Camilla. “...his parents actually thought that their son having a ‘safety valve’ was better than him getting divorced,” reported the outlet.

Still, Prince Philip is reported to have sent Princess Diana a letter shaming his son for the decision to separate. "We never dreamed he might feel like leaving you for her,” he wrote. “I cannot imagine anyone in their right mind leaving you for Camilla. Such a prospect never even entered our heads.”

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Prince Charles and Princess Diana divorced after 15 years of marriage in 1996. Princess Diana died in a car crash the following year. Eight years later, Prince Charles made things official with Camilla, wedding her in 2005. Camilla, whom Charles met several years before his first wife, went on to become the Duchess of Cornwall.

According to E!, it was initially decided that out of respect for Diana, Camilla would be named Princess Consort instead of Queen Consort when Charles took the throne after his mother, Queen Elizabeth II. Though this may no longer be the case, noting, “with the monarchy modernizing at a rapid pace, there are whisperings that enough time has gone by so that Camilla can become Queen Consort.”

Princess Diana and Queen Elizabeth II
Pictured: Princess Diana and Queen Elizabeth II at the Braemer Highland games. Getty Images/AFP