Prince William made a sweet promise to Princess Diana before her death

It has been 20 years since Princess Diana tragically passed away in a car accident in the Pont de l’Alma road tunnel in Paris, France.

Although it has been two decades since her death, her legacy is alive and well, especially in her children. Prince William has often spoken tenderly about his mother,  and now a new story has come out that proves how close the pair really were.

In his book “A Royal Duty,” Princess Di’s former butler Paul Burrell recalls how heartbroken Diana was when Prince Charles stripped her of her title as “Her Royal Highness” during their divorce proceedings. Although even Charles’ mother, Queen Elizabeth II, was willing to allow Princess Diana to keep her “HRH” title, Prince Charles refused. Losing that title would mean that Princess Diana would lose her royal connection to her sons, and would have to curtsy to them at formal occasions.

It might sound a bit convoluted to Americans who aren’t used to the ins and outs of aristocracy, but suffice to say, the loss of her title really hurt Princess Diana’s feelings and proved how much of an outsider she was to her royal relatives.

Upon seeing her so distraught, Prince William came running up to his crying mother, and threw his arms around her neck. He then made her this sweet promise about her lost title: “Don’t worry, Mummy. I will give it back to you one day when I am king.”

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Aw. A true prince in name and in spirit!

There are other juicy details revealed in Burrell’s biography of Princess Di, including the fact that it was Queen Elizabeth who demanded that Charles and Diana quickly divorce when their relationship hit the rocks.

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It seems she wanted to limit drama about the bickering couple in the press, but it is to the queen’s credit that she wanted to allow Princess Diana to keep her title of “Her Royal Highness.”

Although Diana passed away before her son could keep his heartfelt promise, certainly just hearing her eldest son’s kind words brought comfort to her during that stressful and painful time. No doubt Prince William and the Duchess of Cambridge are raising their children, Prince George and Princess Charlotte, to be equally caring and thoughtful.

Related video: 5 great Princess Diana quotes to live by