Edward and Harry have both written their memoirs after leaving the Royal family - although one waited 15 years. Photo / Getty Images
The news that Prince Harry is writing "an intimate and heart-felt memoir" is yet another stinging blow for the Royal family.
After the "truth bombs" that he and Meghan lobbed at the House of Windsor via Oprah – prompting the Queen's exquisite response: "Some recollections may vary" – we might expect some variation in Harry's recollections of his "first-hand account of my life" when it is published next year.
With woeful lack of irony, Harry says that he is "writing this not as the prince I was born but as the man I have become".
A man whom, if he was not born a prince, would not have reportedly been paid an estimated advance of $20 million.
On Friday came reports alleging that the deal is in fact an option for four books, including one to be published after the Queen's death, and the final fee potentially much higher.
A spokesperson for the Sussexes claimed the reports were "false" and insisted that only one memoir was planned. Either way, Harry promises us "a definitive account of the experiences, adventure, losses and life lessons" that have helped shape him.
Yet, aged 36, does he have the reflective maturity and objective distancing that this requires? Sharpening his pencil, he has hired JR Moehringer, the Pulitzer prize-winning journalist and "power ghostwriter", to assist him.
Moehringer ghosted tennis star Andre Agassi's controversial autobiography, Open, in which the former Wimbledon champion admitted: "I hate tennis, hate it with a dark and secret passion and always have."
Goodness only knows what festering sores Moehringer will encourage Harry to divulge.
Speculation has already begun that Harry will detail "whom he blames for Princess Diana's death".
Harry and his edgy ghost would do well to take note of the memoir of Harry's great-great uncle, the Duke of Windsor, which he wrote at the end of the Forties.
Published in September 1951, A King's Story, The Memoirs of The Duke of Windsor, dedicated "To Wallis", caused consternation behind palace walls.
The Royal family were appalled that Edward VIII would sell his secrets for money – he earned £300,000 (roughly £3.5m today) for his bestseller.
Courtiers resented the title because it was Edward's brother, Bertie, who was on the throne thanks to his abdication. However, unlike Harry, who self-exiled from the Royal family 15 months ago, choosing love and family over monarchical duty, the Duke of Windsor waited 15 years before publishing his account of abdicating to marry Wallis Simpson.
By this time, he had given up long-held hope of his wife ever being acknowledged by his family or being accorded the HRH title that he was desperate for her to receive. If the Royal family had welcomed the Windsors back into the fold, it is doubtful that the Duke would ever have consented to this blameless tome.
Edward begins his memoir explaining: "The rule of reticence that binds kings and princes in a constitutional society is not lightly put aside.
It was therefore with some hesitation that I approached the task of writing this book.
However, after the passage of a decade and a half the political passions aroused by the most historically controversial aspect of my career, the Abdication, have long since cooled, and a just perspective of my life and reign should now be possible."
Like Harry, the Duke chose an American ghostwriter, Charles Murphy. Murphy had also been a successful journalist – he was the former Washington bureau chief for Fortune Magazine – who turned to ghosting.
He wrote pioneer explorer, Admiral Richard Byrd's account of his expedition to Antarctica but it was his three-part series for Time magazine on Winston Churchill, written during World War II, that really caught the eye of Edward, who asked to meet him.
Initially, Murphy persuaded the Duke to collaborate while he was governor of the Bahamas on four articles for Life magazine, for which Edward earned $25,000.
These were gossipy in tone rather than a savage attack on his family who had dispatched him to a life of empty exile after the abdication.
Instead, readers were treated to anodyne accounts of how many suits he owned and why the Duchess of Windsor always beat him at cards.
Still, it was deemed sensational to learn that the former king had brought a collection of cigarette lighters with him to Government House, Nassau, along with his gold and red Field Marshall's baton which he used to point at maps, because it offered a rarely glimpsed peek at royal life.
A few years later his memoir, A King's Story, was published. The Royal family and courtiers were incandescent.
Lady Hardinge, wife of the Duke's former private secretary wrote: "While his family held its peace, he apparently found it necessary to exchange a highly coloured and, in my view, one-sided account of his abdication for a large cheque." The Queen Mother never forgave the Duke for the terrible timing – the British launch of the book coincided with the final collapse of her husband Bertie's health.
He died five months later.
Of the Duke's memoir, royal intimate Lady Donaldson, who later wrote a biography of the Duke herself, said: "Behind the scenes, the book caused unrestrained anger and concern."
You can imagine a similar fear at Buckingham Palace that Harry will pour forth more embarrassing and painful details for his father, brother and the Queen, as he pens "his truth".
As well as an age-old sense that any royal memoir is a betrayal of the family's values and their duty to their sovereign, the Duke of Windsor and Harry also share, along with their love and loyalty to their dominant American wives, an ambivalence about their heritage. The emotional cost of service superseding family life clearly rankles.
Harry bleated to Oprah: "When it comes to parenting, if I've experienced some form of pain or suffering because of the pain or suffering that perhaps my father or my parents had suffered, I'm going to make sure I break that cycle so that I don't pass it on."
In the chapters on his childhood, in which the former King memorably described Christmas at Sandringham as "Dickens in a Cartier setting", Edward writes: "For better or worse, royalty is excluded from the more settled forms of domesticity.
"While affection was certainly not lacking in my upbringing, the mere circumstances of my father's position interposed an impalpable barrier that inhibited the closer continuing intimacy of conventional family life." The Duke wrote that "the concept of duty that was drilled into me, and I never had the sense that the days belonged to me alone", echoing Harry's sentiment that "my father and my brother, they are trapped".
Harry promises in his book, however, that: "I can help show that no matter where we come from, we have more in common than we think." Edward similarly writes that his "birth and title should not set me apart from other people".
The big difference here though is that the Duke of Windsor had allowed enough time to pass between the rupture of the abdication and going to press and this produced a more measured book that never sought to undermine the institution of the monarchy.
Unlike Prince Harry's moaning, for a man as impassioned and aggrieved as Edward was, no animosity is tangible in his prose. No family member is discredited.
Of his mother, who refused his plea to meet Wallis, which hurt him deeply, he generously explained: "It was not, I was sure, because they were wanting in understanding: it was rather because the iron grip of Royal convention would not release them."
Edward's dislike for Prime Minister Stanley Baldwin, who sought to rid him from the throne, is apparent but the book is a masterclass in understatement. After he has given his abdication speech, Edward describes bidding his brothers, then his beloved country, farewell. It is beautifully pointed when the man who had ruled an empire of over 400 million people describes leaving his country "unescorted".
"And so it came to pass that at 2 o'clock on the morning of December 12th, 1936, HMS Fury slid silently and unescorted out of Portsmouth Harbour.
"Watching the shore of England recede, I was swept by many emotions. If it had been hard to give up the throne, it had been even harder to give up Great Britain. I knew now I was irretrievably on my own. The drawbridges were going up behind me.
"But of one thing I was certain; so far as I was concerned love has triumphed over the exigencies of politics.
"Though it has proved my fate to sacrifice my cherished British heritage along with all the years in its service, I today draw comfort from the knowledge that time has long since sanctified a true and faithful union."
In contrast with Harry's alleged book deal, the memoir was the last word that the Duke ever wrote on his life or the abdication. He died 21 years later.
He did not detail his bitterness over his life in exile, nor his pain towards his unyielding family. Judging by his recent form, such restraint seems unlikely with the memoir that Harry will produce. If only the Duke of Sussex would take note.
Once the royal drawbridges have gone up behind you, in literary terms, less is always more.
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