"I often say to my girls, I've been there and made the mistakes so they know what not to do." Photo / Getty Images
Proof – if further proof were needed - that the Duchess of York is the gift that keeps on giving, the Empress Fergiana has been opining on the extent to which our young royals can learn from her mistakes, manifold as they are.
During an interview on Good Morning Britain, it was put to her that she and Diana, Princess of Wales, had served as the monarchy's "guinea pigs", and that the next generation would endure the same pitfalls along with the added pressure of social media.
The UK's favourite ginger nut concurred, noting: "I often say to my girls, I've been there and made the mistakes so they know what not to do. It's really cool, actually. All I can say to anyone, including my girls, is: 'Be who you are'." She also recommended remembering the names of people who open doors for them and cook their food, which feels fabulously #aristocraticproblems.
How heartening to think that Kate, Meghan, Euge and the like can simply take a look at what the artist formerly known as Sarah Ferguson did, then do the exact opposite. That said, couldn't we all benefit from a list of Fergie's Don'ts?
Perhaps it could even become her next publication, say: The Bumper Book of Fergie's Foibles and Failures? Said tome could kick off with our heroine's top five Don'ts: the pick of the crop, the What-the-Hell-Were-You- Thinkings from which all other duff decisions follow.
1. Do not, under any circumstances, be who you are
As ever, the duchess's comments provide a splendid example of how not to play things. One does not join The Firm to be who one is. One joins The Firm to say nothing while working incredibly hard at the most banal of tasks in a way that strikes some as metaphysically important, others as entirely useless.
Surface gloss should be considered a plus, actual personality to be avoided. Fergie remarked of the Queen: "I think she knew me as a little naughty aged 10. I still am a little naughty aged 10." One only has to glance at the duchesses of Cambridge and Sussex to know that minxish kidult is not what the Windsors are looking for. Instead, think: impeccably coiffured blank canvas.
2. Do not allow yourself to become unprincessily chunky
Shortly after her nuptials, Fergie's weight rose to almost 16 stone (100kg), leading the tabloids to re-name her the "Duchess of Pork," a moniker she later monetised in her capacity as a Weight Watchers spokeswoman.
Again, wrong. Popular princessdom comes slim: not so skinny as to make people worry, but slender enough for them to ask: "How does she do it?" and deem such slenderness born of tiara wearing and moonbeams. Your job is to wear clothes that can be criticised by a carping public: a spare tyre will only obscure matters.
3. Do not become the poster girl for obscure sexual fetishes
Back in 1992, it was still considered risqué for married couples use each others' Christian names.
Imagine the shock, then, when newly-separated Sarah Ferguson was photographed topless sunbathing while having her toes sucked by her financial adviser.
Later, when culture minister David Mellor was accused of a "toe job", the tabloids were forced to add in the made-up-fact of his sporting a Chelsea kit to top Fergie's staggering perversion. Sex should be reserved for procreative purposes: duchesses do not stray off piste.
4. Do not get a divorce
Haven't you watched The Crown? Don't you know the mess all this can cause? The awkwardness and embarrassment attendant upon what to call you, where you'll live, whom you choose to hook up with, and how you will be financed. Better surely to adopt the traditional royal route of playing happy families when constitutionally required no matter how venemous you may feel towards your other half.
5. Do not, repeat not alienate the Duke of Edinburgh
Schoolgirl error ahoy! Prince Philip is not only the power behind the throne, he's a hoot, a card, has been there himself, and knows that the consort's path tends to come speckled with corgi turd. For heaven's sake, get this chap on board. Feign an interest in carriage driving, whatever it takes.
Here is a man of intelligence who has put up with decades of opening biscuit factories without surrendering his sanity; a chap whom a posse of Pacific Islanders believe to be the penis-gourd-sporting Melanesian Messiah; the backbone of the House of Windsor, who may yet outlive us all. Philip should be your oracle, not someone who regards you as "pointless".