In a bombshell revelation that rips open old wounds, a royal author has claimed that Princess Diana went to her grave still furious with her former best friend and sister-in-law Sarah Ferguson over one particularly vicious allegation in Fergie’s explosive 1996 memoir.

The late Princess of Wales, who once shared a close and playful bond with the Duchess of York, allegedly never forgave Sarah for what she saw as a cruel and self-serving betrayal — an allegation that cut deep into Diana’s already fragile emotional state in the final year of her life.

The Allegation That Destroyed Their Friendship According to royal biographer and expert Andrew Morton, who has written extensively on the royal family, Diana was deeply hurt by a specific passage in Sarah Ferguson’s memoir My Story. In the book, Fergie allegedly made damaging claims that Diana had been involved in leaking negative stories about her to the press — something Diana vehemently denied and viewed as a stab in the back from one of her closest confidantes.

The two women had once been inseparable — giggling together at royal events, supporting each other through difficult marriages, and even sharing secrets about life inside the Firm. But by 1996, their friendship had completely collapsed, and Diana reportedly told friends she felt “betrayed” and “deeply wounded” by Fergie’s words.

Morton claims Diana never reconciled with Sarah before her tragic death in Paris in August 1997. The Princess carried the hurt with her to the end, believing her former friend had thrown her under the bus to sell more books and salvage her own damaged reputation.

Fergie’s Long Pattern of Self-Serving Behavior This latest disclosure fits a well-established pattern for Sarah Ferguson. The Duchess of York has repeatedly been accused of monetising her royal connections while causing chaos within the family. From her toe-sucking scandal with financial advisor John Bryan to her endless money-making schemes, Fergie has often put her own interests first — even at the expense of those closest to her.

Diana, who was already battling intense media scrutiny, eating disorders, and a crumbling marriage to Prince Charles, reportedly saw Fergie’s memoir as the final straw. Friends of the late Princess claimed she felt “stabbed in the back” by someone she had trusted and supported during her own darkest times.

The Irony of Fergie’s Current Situation The timing of this revelation is particularly savage. Sarah Ferguson is currently trying to distance herself from her disgraced ex-husband Prince Andrew amid his ongoing legal troubles. Having once defended him fiercely, she is now reportedly viewing him as “toxic” and damaging to her own branding opportunities.

Many royal watchers see a poetic justice in this. The woman who allegedly betrayed Diana for personal gain is now facing similar isolation and reputational damage. As one commentator noted: “Fergie made a career out of selling royal secrets and drama. Now the drama is coming for her.”

Diana’s Unforgiving Final Years Princess Diana’s final years were marked by emotional turmoil, new relationships, and a desperate search for happiness away from the royal institution. The alleged betrayal by Sarah Ferguson only added to her sense of isolation. Diana, who had once been a supportive friend to Fergie during her own marital crises, felt the memoir was a gratuitous and unnecessary attack.

Insiders claim Diana privately told friends that she would never trust Sarah again. Their once-warm relationship ended in bitterness and silence — a rift that was never healed before Diana’s tragic death at just 36 years old.

A Friendship Built on Sand What began as a seemingly genuine sisterly bond between two women who married into the royal family under immense pressure ultimately collapsed under the weight of ego, ambition, and self-preservation. Sarah Ferguson’s decision to include the controversial allegation in her memoir has now been revealed as a pivotal moment that destroyed one of the most high-profile friendships of the 1990s.

As the royal family continues to deal with the fallout from various scandals, this latest disclosure serves as a stark reminder of how quickly alliances can crumble when personal gain is prioritised over loyalty.

Princess Diana may be gone, but her hurt and disappointment over Sarah Ferguson’s alleged betrayal still echo through royal history. For Fergie, the price of that one “serious allegation” may have been the permanent loss of a friend — and a stain on her legacy that no amount of rebranding can fully erase.