Inside Prince Philip's Relationship With Princess Diana
Prince Philip and Princess Diana had a close, occasionally rocky relationship before the latter's life was tragically cut short. According to People, the two saw themselves as outsiders to the Royal Family, and bonded over those mutual feelings. Diana found comfort in her father-in-law Philip whenever she struggled with the restrictions of the royal life, as Philip had married into the family and could understand what she was going through. She often sat next to Philip at dinners rather than her husband, Charles.
This perhaps foreshadowed the difficulties Diana would have in her marriage. Philip wrote private letters to Diana, sympathizing with her struggles but still encouraging Diana to save her marriage. The attempts were in vain, however, and the rift in Diana's marriage led to a rift between her and her father-in-law as well. Though she appreciated his obviously genuine care, and found him an entertaining dinner guest, as a father-in-law, Philip was too judgmental for Diana's tastes.
Philip's letters eventually angered Diana
While Diana was appreciative of Prince Philip's advice and help with her marriage, especially as he originally placed most of the blame on Charles, their correspondence soon soured (via Elle). The cause was a shift in Philip's tone, labeling Diana as irrational and jealous and the true cause of her marital struggles. Another letter essentially told her that this stress was part of life in the royal family, and was something she would have to get used to.
In the end, their relationship was complicated, as was much of Diana's much-publicized life in the royal family. Philip had sympathy and admiration for Diana. No doubt he was reminded of his first years after marrying into the British royal family. He was certainly appreciated and loved by Diana at first, who addressed him as "Pa" in her letters. However, as Diana's marriage fell apart, so too did her love for her father-in-law, as the one person who she felt understood her eventually turned against her.