The special connection between Prince Philip and Princess Diana is being remembered as the royal family prepares for the Duke of Edinburgh's funeral Saturday.
Twenty-four years after Philip gave his grandsons strength by joining them as they walked behind Diana's coffin at her 1997 funeral, Prince Harry and Prince William will likely return the honor by walking behind Philip's coffin during the ceremony inside Windsor Castle this weekend.
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A glimpse into the relationship between the brothers' mother and grandfather was given during a 2007 inquest into Diana's death in a car crash in Paris. The proceedings revealed letters between Philip, who died at 99 on April 9, and his daughter-in-law that he sent as her marriage to his son Prince Charles was faltering.
According to The Associated Press, Diana refers to Philip as "Dearest Pa" in the letters from 1992, and the duke offers to help try to patch up her marital problems.
"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 talents as a marriage counselor!!!" he wrote, signing the letter "With fondest love, Pa."
"I was particularly touched by your most recent letter, which proved to me, if I didn't already know it, that you really do care," Diana responded. "You are very modest about your marriage guidance skills, and I disagree with you."
Diana and Philip had a common bond in that they were both outsiders to the British royal family.
Philip, who married Queen Elizabeth II in 1947, was born to Greek aristocracy before his family was exiled from the country. Diana also married into the royal family after growing up in an aristocratic family.
"He tried to help her understand what it was like to marry into this institution," NBC News British historian Andrew Roberts said on TODAY Wednesday. "This family, but also this institution. She was very thankful to him."
Scenes of the connection between the two were also portrayed in season four of the hit Netflix series "The Crown." British actor Tobias Menzies, who played Philip in seasons three and four, told Vanity Fair that a person in production had gotten copies of some of the old letters between Diana and Philip.
"I was really struck by the kind of balanced, calm, quite tender kind of atmosphere to those letters," he said. "He clearly, behind the scenes, worked quite hard to mend that relationship. And if those letters are anything to go by, he does seem to have been a keen supporter of hers."
There were also accusations of Philip expressing his displeasure with Diana. According to the AP, her butler, Paul Burrell, told police that while some letters were nice, others were "cutting and cruel." Philip had denied media reports about the alleged derogatory letters to Diana in an official statement in 2002.
"The original letters sent by Prince Philip to the Princess have apparently been lost, but he kept copies of his letters to her and he also has the original replies from the Princess," the queen's press spokesman said in a statement at the time. "He started the correspondence in June 1992 in a friendly attempt to resolve a number of family issues which arose at the time leading up to the official separation of the Prince and Princess of Wales in December of that year."
"Prince Philip wishes to make it clear that at no point did he ever use the insulting terms described in the media reports, nor that he was curt or unfeeling in what he wrote," the spokesman continued. "He regards the suggestion that he used such derogatory terms as a gross misrepresentation of his relations with his daughter-in-law and hurtful to his grandsons."
Philip's grandsons are now together again for his funeral, marking Harry's first time back with his family in the United Kingdom since his bombshell interview with Oprah Winfrey last month. William and Harry are expected to be part of the formal proceedings inside Windsor Castle, which will be very different from the large public funeral of their mother in 1997. Saturday will be a much more private ceremony than the usual royal funeral due to the pandemic.