Princess Diana never forgave Sarah Ferguson for one betrayal that ended their friendship: book
Princess Diana and Sarah Ferguson were once inseparable, famously dubbing themselves the "Terrible Twins" and the "Wicked Wives of Windsor." But a devastating rift between the royal rebels ended their friendship for good.
The claim comes from royal author Andrew Lownie, whose expanded edition of "Entitled" delves deeper into the lives and controversies surrounding the former Duke and Duchess of York.
Fox News Digital reached out to Ferguson's spokesperson for comment. A spokesperson for Buckingham Palace previously told Fox News Digital it does not comment on books.
"The two women, once close, had not spoken for months after Sarah had written about her sister-in-law, against Diana's wishes, in her memoir and made a joke about catching a verruca (wart) from one of Diana's shoes," Lownie wrote.
"The two were fourth cousins and had known each other since they were teenagers — their mothers had been at school together — and shared the experience of their mothers being denied custody of their children."
Lownie claimed that the sisters-in-law never reconciled after Sarah's 1996 memoir, "My Story," was published. Diana died in 1997 at age 36 from injuries sustained in a Paris car crash.
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Royal expert Richard Fitzwilliams told Fox News Digital that Diana suspected Sarah of "selling stories" and was reportedly "angered by mentions of her sons in the book."
Diana ignored Ferguson's apologies, Fitzwilliams claimed, adding, "If she had wanted to renew their friendship, she would have."
British broadcaster and photographer Helena Chard told Fox News Digital that the fallout wasn't just the result of a tell-all.
"It was the bigger picture that prompted Diana to cut ties with Sarah," Chard explained. "They'd survived a huge amount together. However, the memoir brought their private tensions into public view. It was the final straw, and alarm bells rang as Diana read conversations referring to her sons."
"Diana's privacy was her safety," Chard shared. "She felt Sarah was leaking personal information and trading on their conversations. Diana was fastidious about controlling her narrative. She used private information strategically.
"Diana felt 'Calamity Jane' Fergie, the great storyteller, was capable of revealing deeply personal details that could negatively affect her life. In Diana's mind, she had no choice but to cut ties with her once-trusted partner in crime and kindred spirit. She was protecting her image."
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Lownie wrote that Diana and Sarah were friends long before they became royal wives. By the time Diana married then-Prince Charles in 1981, Sarah was already part of her social circle. Diana was said to be "in need of an ally" as she navigated royal life and "had already tried to make Sarah Ferguson one of her ladies-in-waiting."
Lownie claimed it was Diana who played matchmaker, bringing Sarah and the former Prince Andrew together. The couple went on to marry in 1986.
"Diana and Sarah were famously close as the two 'outsiders' in 'The Firm,'" Fitzwilliams explained. "They plotted together against an establishment they both found confining."
"Both from aristocratic backgrounds, they became as thick as thieves," Chard said. "They were each other's confidante and wingwoman, especially after marrying into the British royal family."
Both women endured turbulent marriages that played out on the world stage while raising two children. They were also targeted by the British press. Charles and Diana announced their separation in 1992, and their divorce was finalized in 1996. Following immense tabloid scrutiny and time apart, Andrew and Sarah separated in 1992, with their divorce also finalized in 1996.
Diana reportedly called Sarah the "canary in the coal mine," seeing her as a cautionary tale of what happened when a royal wife fell out of favor. As Sarah endured relentless tabloid ridicule and growing isolation from the royal fold, Diana feared she was watching her own future unfold in real time.
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Then came the books.
Diana secretly collaborated on Andrew Morton's 1992 bombshell "Diana: Her True Story," using it to expose her battles with bulimia, mental health struggles and a deeply troubled marriage.
Although Sarah reportedly intended references such as borrowing Diana's shoes to be humorous, royal commentators said Diana found the passage deeply hurtful. They suggested the episode left Diana feeling that a longstanding bond of trust had been broken.
"If Diana had lived, I believe they would have reconciled," Chard said. "[But] they were on different paths, with Diana also being the mother of the heir to the throne. Together, Diana and Fergie had been through so much. They valued loyalty once it was earned. With time and conversation, I believe they would have come to an understanding, as they were comrades in arms for the best part of their lives."
Royal broadcaster Ian Pelham Turner claimed that Diana's final years were marked by growing mistrust and anxiety. She became increasingly concerned about leaks from within her inner circle and believed that powerful forces were seeking to undermine her.
"She could not trust anyone," he said. "So, in some ways, self-isolation was necessary in her mind, including her friendship with Sarah. And Sarah’s book did not help matters, almost confirming the emotions in Diana’s mind. Should Diana have been alive today, personally, I feel the friendship with Sarah would have rekindled. An older and wiser Diana would have found peace and real love with another."
In 2011's "Finding Sarah," the former duchess admitted she and Diana had not spoken for a year before the princess died.
"I never knew the reason, except that once Diana got something stuck in her head, it stuck there for a while," Sarah wrote, as quoted by People magazine.
"I wrote letters, thinking whatever happened didn’t matter, let’s sort it out," she wrote. "And I knew she’d come back. In fact, the day before she died, she rang a friend of mine and said, ‘Where’s that Red? I want to talk to her.’
"In any sibling relationship, there are ups and downs and peaks and troughs, but we were always steadfast in our friendship. We never let the sun go down on too many heated discussions. Our bond was never broken."
Their friendship may have fractured in Diana's final years, but Sarah has spent decades keeping her friend's memory alive. Chard noted that Sarah remains a vocal defender of Diana's legacy, a view she expressed to Fox News Digital in 2023.
"I think people might be surprised to know how hilarious she was," Sarah said of her friend "Dutch" at the time.
"There was no one who could make me laugh harder or more immediately than Diana. She was incredible and one of life's true soul mates for me."