Queen Elizabeth II, Prince Charles, Princess Anne
Prince Charles was furious at Princess Anne for tying the knot before him. Pictured: The Queen, Prince Charles, Princess Anne watch the 2017 Braemar Gathering at The Princess Royal and Duke of Fife Memorial Park on September 2, 2017 in Braemar, Scotland. Getty Images/Chris Jackson

Prince Charles was reportedly furious with his younger sister, Princess Anne, for doing something before him.

In the documentary “The Royal House of Windsor,” it was revealed that the future king wasn’t pleased when he learned that Princess Anne would wed before him. Prince Charles penned a letter to one of his friends and said that he felt the urgency to preserve his position within the royal family.

“I can see I shall have to find myself a wife pretty rapidly otherwise I shall get left behind and feel very miserable,” he said (via Express).

Prince Charles’ furious reaction was made six months after Princess Anne tied the knot with Mark Phillips, an Olympian, at Westminster Abbey in 1973. According to the Netflix documentary, Prince Charles dated approximately 20 women after he split from Camilla Parker Bowles. The Duchess of Cornwall tied the knot with another man in 1973.

Years after Princess Anne’s wedding, Prince Charles decided to marry Princess Diana at Westminster Abbey in 1981. However, their marriage didn’t last. The ex-couple was blessed with two children, Prince William, and Prince Harry.

In 1992, the royal family revealed that they are aware of Prince Charles and Princess Diana’s troubled marriage. In fact, Prince Philip even wrote a letter addressed to Princess Diana.

“I can only repeat what I’ve said before if invited, I will always do my utmost to help you and Charles to the best of my ability. But I am quite ready to concede that I have no talent as a marriage counselor. Charles was silly to risk everything with Camilla for a man in his position. We never dreamed he might feel like leaving you for her,” Prince Philip wrote.

And a year before Prince Charles and Princess Diana’s divorce was finalized, the Princess of Wales sat down for an interview with Panorama where she said that she knows her husband was having an affair with Bowles.

“There were three of us in this marriage, so it was a bit crowded,” she said.