The British royal family have, throughout the ages, had a long genetic history of haemophilia, weak chins and an uncomfortable fascination with fascism. (Maybe it's the uniforms? They do like a crisp salute and a well-cut jacket.)
But there is another much lesser-known affliction that seems to keep recurring throughout the generations, something I like to call the Princess Paradox. That is – the shorter the stint of a woman who marries into the royal family, the greater the carnage she wrecks on The Firm.
Sarah Ferguson, Duchess of York lasted only five years but her toe-sucking-sucking, royal-access-selling, reality-TV-filming ways are the stuff of legend.
Diana, Princess of Wales only did marginally better hit 11 years before separating from Prince Charles but her stint as an HRH caused a sonic boom that shook the crystal and rattled the china, the ripple effects of which are still being felt today.
But of course the absolute, undefeated nonpareil here is Meghan, Duchess of Sussex. She didn't even make it to her second wedding anniversary before bailing on royal life and going on to help launch the most blistering attack on Buckingham Palace since the Luftwaffe refuelled.
At every turn, the former Suits star and her husband Prince Harry have outplayed and outmanoeuvred a royal outfit which still appears to be operating from the same dog-eared 1953 playbook they used when Princess Margaret kept disappearing into locked rooms with Group Captain Peter Townsend.
But this week, the Sussexes might have just met their match.
Entering the ring, weighing 42kg, standing five-foot-tall and carrying an antique Scottish walking stick, it's the Buckingham Bruiser, the Windsor Welterweight, the Balmoral Belter ... Her Majesty the Queen!
The thing I'm wondering today is, has the 96-year-old just outsmarted Harry and Meghan?
This week, the Duke and Duchess were back doing what they do best: Giving incendiary interviews and wearing tens of thousands of dollars' worth of designer clothes to a charity event.
They were, of course, in the Netherlands for the Invictus Games, the sporting championship for wounded military personnel, both veterans and those still serving, that Harry founded to universal acclaim in 2014.
With the spotlight back on the duo, and the world's media keenly celebrating the success of the Games, Harry managed to derail things entirely when he sat down with the US Today show and self-importantly told the world he had visited his grandmother in Windsor to "make sure she's protected and got the right people around her".
Hearing this, the whole world seemed to respond in a collective gasp of total incredulity- YOU? YOU? think you're protecting her? The same grandson and granddaughter-in-law who went on global TV screens to paint the royal family as institutionally racist and unfeeling while the Queen's husband was in hospital? (Prince Philip passed away exactly one month after it aired.)
This is the Sussexes' superpower – their ability to take any situation and make it somehow about their own psychodrama, thus ensuring the entire situation devolves into 48-point font red headlines and a flurry of angry opinion pieces. They could personally cure cancer and solve the Middle East peace process and still find a way to somehow make the whole thing about their supposed victimhood.
The line that Harry and Meghan have been energetically peddling for what feels like about 67 years now (remember their 2019 interview in which Meghan said FEELING?) is that they have been treated horribly by the big, bad palace; that they are casualties of the pinstriped royal machine.
Which is to say, Harry and Meghan have proven spectacularly adept at taking charge of the narrative.
Which brings us to the Queen's masterstroke, her knockout move.
In only six weeks, the eyes of the world will be on London for the Platinum Jubilee celebrations, set to take place over a special four-day long weekend in early June. The schedule is a mixture of official and family events, with the key moment being when Her Majesty gathers her family to wave to the crowds from the Buckingham Palace balcony.
The big will-they, won't-they question here is, will Harry and Meghan show up?
It is now looking like the Queen could have stealthily taken control of things, thus ensuring that PR-wise, she will come out on top whether the Californian branch of her family deigns to roll up or not.
See, earlier this week, the Telegraph reported that the Sussexes have been "invited to appear" on the palace balcony with la famille Windsor and to be a part of the family events on the slate (as opposed to official moments such as the Trooping the Colour procession).
While that story soon got overtaken by the flap over Harry's Today interview, what has been largely overlooked is what a canny move this was. It was most interesting, shall we say, that only days after Harry and Meghan "stopped by the UK", as their spokesperson put it, that this balcony invitation just happened to be made public.
If this did come from the palace, then what the Queen has essentially done is back Harry and Meghan into a corner.
The invitation makes the 96-year-old look magnanimous and big-hearted, willing to overlook the Sussexes' made-for-TV truth-telling. Here she is, in the twilight of her reign, offering her errant family members who have caused no end of heartache a huge olive branch.
Therefore, if Harry and Meghan do appear on the palace balcony in June, it will look like they are there courtesy of her beneficence.
And if they don't go to London for the Jubilee? The Sussexes will appear even more churlish and childish, willing to put personal grievances ahead of helping his grandmother and former boss celebrate her landmark 70 years on the throne.
To be fair though, there are a number of other factors complicating le grand Jubilee question.
To start with, there is the issue of Wall Street's current whipping boy, Netflix. Will the Sussexes' TV masters, who are ever more desperate to strike streaming gold, get any sort of look in during the Jubilee?
The Sun has reported that "there are fears within the Royal Family that Netflix could apply pressure to film the Sussexes at the Queen's celebration".
Meanwhile, according to the Telegraph, there have been "suggestions that further details of the couple's meeting with the Queen, which was described as 'private' by palace officials, may emerge in the documentary Heart of Invictus".
Royal commentator Charles Rae has said during a radio interview: "The Netflix film crew will most certainly favourably capture Harry and Meghan. It will look as if they are still members of the Royal family when they are private citizens. That will be the whole aim to show people they are still considered very important people."
Then there is Harry's current legal stoush with the UK's Home Office over the decision for his official protection being withdrawn when he and Meghan quit official royal duties.
When asked by Today's Hoda Kotb about whether he was planning on celebrating the Jubilee, Harry said: "I don't know yet. There's lots of things, security issues and everything else.
"So this is what I'm trying to do, trying to make it possible that I can get my kids to meet her [the Queen]."
One thing is for sure: come the first weekend in January, Netflix's viewing figures could take a serious hit because there will only be one show in the world worth obsessively watching. Stay tuned ...