Diana's treatment will always be a stain on the royals - no matter how hard they try to erase it

Twenty-five years on from her tragic passing and the impact of Diana’s storied life remains as strong as ever.

From the steady stream of documentaries and movies sharing her life with new audiences, to the generation of young people who echo her principles and values through her namesake charity – the Diana Award – the short life of the People’s Princess has left an everlasting legacy.

Archival footage in recent documentaries, including HBO’s immersive feature The Princess, are also a reminder that in the two-and-a-half decades since her passing at 36, she still remains mourned by many.

However, 31 August has also become a day that the institution of the monarchy has often come to dread. Though Diana’s humanitarian work and public service are universally celebrated, it is her personal life that some within the palace still want to forget; an annual reminder of the institution’s indifference and out-of-touch practices during the most difficult and tortured days of her life.

As Diana claimed after her separation from Prince Charles, it was members of the same Royal Household that attempted to curtail the very role we celebrate today. She claimed charitable visits abroad were blocked, private letters intercepted and cruel attacks in the press encouraged. She was the Royal Family’s biggest threat – one that needed to be muzzled.

Of course, you wouldn’t catch a whiff of this stained history if you stepped into one of the many Diana-centred exhibitions held at royal palaces (or their official gift shops, which still carry memorabilia in her name for profit). Her pain may be ignored, but a slice of the love and adoration she still receives will always be nice (even better with a little revenue). After all, the late princess is why so many people around the world are interested in the Royal Family in the first place.

In the royal bubble, the memory of Diana’s life has been edited and perfectly curated to suit the Firm. Any evidence of the grim reality of her royal existence or the mistakes made that lead to her tragic end are impossible to find.

“Sanitised history, if you will,” a former aide tells me. “To the institution, Diana will always be remembered in a way that is safe for them – a safe distance kept from everything else. It’s why you never see Charles acknowledge the anniversary of her death. Quite simply, they can't afford to remind people of his role in her pain.”

It’s a “recollections may vary” approach to handling royal scandal and shame that continues to this day. When Netflix released The Crown’s fourth season, it prompted orchestrated efforts by palace aides and royal-adjacent media outlets to call into question the historical drama’s depiction of the past.

A show once adored by family members (a “brilliant bit of PR” for the Firm, an aide remarked to me in 2015) had become the enemy after Diana’s narrative entered the storyline.

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Sure, most of the show’s dialogue has been reimagined and some moments fabricated, but a lot of the who-what-where-and-when of it all comes straight from Diana’s own mouth and the very news coverage written by outlets now jumping to defend the Palace.

In just over eight weeks, the series’ fifth instalment will be released, with episodes focusing heavily on Prince Charles’ affair with Camilla Parker Bowles and Diana’s suffering. To say that staff at Clarence House are concerned about its negative impact on the future king’s popularity is an understatement (things got so bad during the previous season that they had to temporarily shut down the ability to comment on their Instagram account).

Of course, it would be wrong to say that the monarchy hasn’t evolved at all since her death. The past quarter-century has seen a huge improvement in royal image management, presenting a more modern monarchy and a more caring approach to royal duty, thanks to important work tackling the stigma around issues such as mental health, domestic violence and conflict-related sexual violence. Even elements of the warm human touch Diana brought to her duties have been adopted by a number of the family members.

However, the poor management of Prince Andrew’s sordid scandals and the Sussexes’ claims of institutional cruelty and racism show that many post-Diana lessons have yet to be learned. In many ways, the House of Windsor has still yet to properly handle the crisis or the challenge of a modern woman within their quarters.

Listening back to Diana’s stories today, that lack of change (and accountability) is evident, some of it echoing recent comments made by the Duchess of Sussex.

“I have been battered, bruised and abused mentally by a system for 15 years now, but I feel no resentment . . . I am strong inside and maybe that is a problem for my enemies,” Diana wrote in a letter 10 months before her death. “Thank you Charles for putting me through such hell and for giving me the opportunity to learn from the cruel things you have done to me.”

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No messenger to accuse of twisting her quotes, no BBC journalist to blame for her “paranoia”, this is just Diana in her own words. And it’s those words that, even today, the Royal Family can’t escape or truly erase.

“She won't go quietly, that's the problem,” Diana once said of the palace's problem with her. “I'll fight to the end, because I believe that I have a role to fulfil.”

Thanks to Princes William and Harry, that role continues to be fulfilled through their philanthropic work today. As for going quietly? Never. Diana’s voice is as strong as it’s ever been.