On February 6, 1952, the day King George VI died and Queen Elizabeth became monarch, the sixth in line to the throne was five-year-old Prince Richard.
On Prince Charles and Lady Diana Spencer's wedding day in 1981, the number six spot was held by Zara Tindall.
In September 1984 when Prince Harry of Wales arrived in the world, it was his aunt Princess Anne, the Princess Royal's turn to be bumped down to the lowly position.
The sixth in line to the throne is not meant to matter. Usually.
Traditionally, being sixth notches below the crown makes a Windsor little more than a monarchical safety clause, a genetic backup if you will, in case something truly woeful should happen.
But if there is one thing we can say about Prince Harry, it is that the man has quite the habit of being the exception that breaks the rules.
He might currently occupy the inglorious sixth position, having been edged further and further away from any chance of ever ruling with the arrival of his niece and nephews, however he retains an out-size sway over the royal family.
Somehow, despite he and his wife Meghan, the Duchess of Sussex officially walking away from royal life last year, the couple still manage to exert an unprecedented and hitherto inconceivable influence over the palace.
This fact was on full display on Friday in London when Harry and William were briefly reunited for the unveiling of the statue they had commissioned way back in 2017 of their mother Diana, Princess of Wales.
Only a small clutch of people, including Diana's sisters and brother, gathered to watch the Wales men debut the Ian Rank-Broadley piece that depicts their mother — a far cry from any stock standard royal outing.
Relatively short, sharp and with no speeches or live cameras, the engagement could not have been more different from the last time Harry was photographed in the palace's Sunken Garden, namely during his and Meghan's giddy engagement photocall in November 2017.
Gone was the retinue of correspondents from mainstream British outlets who normally cover such events.
Earlier this week the Daily Mail reported that Harry had wanted "his own journalist to cover the day". That is, having long taken a critical view of the British media establishment, the now California-based prince did not want "to leave the statue unveiling at Kensington Palace to the official 'Royal Rota' of journalists".
In January 2020 when the Sussexes first announced they were quitting, they also indicated that they would be "be adopting a revised media approach to ensure diverse and open access to their work" and would "no longer participate in the Royal Rota system".
That the mainstream press was not involved on this occasion, only Harry's second time back on British soil and the first event over which he had any say post-Megxit, is particularly noteworthy.
While the Cambridges have a much healthier working relationship with the Fourth Estate, that things proceeded in line with Harry's stance on the media seems highly unlikely to be an accident.
So too was the no show of William's wife Kate, Duchess of Cambridge.
Despite the event taking place in the grounds of Kensington Palace, that is the West London estate where the Cambridges live in a 20-room, four-storey apartment, she did not take part in the ceremony.
Her non-attendance was a marked departure from August 2017 when it was the erstwhile trio of the Cambridges and Harry who joined forces to visit the memorial white garden planted to mark 20 years since Diana's death, the last big public occasion to honour the princess' life and legacy.
This time around, Kate was nowhere to be seen, with her conspicuous absence from proceedings reading like a diplomatic sop to the Sussexes. Meghan, having only given birth less than a month ago, was unable to attend.
"Aides had agonised over whether Kate, 39, should attend," the Telegraph's Camilla Tominey reported.
"While William, 39, always wanted his wife of 10 years to be by his side, there were concerns that Harry might feel 'outflanked' by the Cambridges if they were there together, and he was on his own."
What is so interesting here is Team Cambridge's willingness to make concessions and to placate the fractious Sussexes despite the series of royal-baiting interviews they have given in recent months.
On William and Kate's part, this surprising change of tack might be less a wholesale capitulation to the trenchant Sussexes than a strategic retreat. That is, this was a temporary cessation of hostilities to ensure the statue unveiling went off without a hitch and that the focus was on Diana, not the brothers' ongoing drama.
That said, the bigger picture here is that it is unquestionably in the Cambridges' interest to find a way to move on from the turbulent years of Sussex-related histrionics gobbling up all the media oxygen.
Unfortunately for William and Kate, the ramping up of their large-scale charitable projects over the past 18 months has nearly perfectly coincided with Harry and Meghan's Megxit soap opera.
If the Cambridges want the world, or at least the UK and the Commonwealth, to start paying more attention to the things they are energetically trying to achieve, they need the Sussex circus neatly packed up. Quick sticks.
However, while William might have waved the white flag for this week's ceremony, it would seem that we are a long way from some new-found era of princely peace breaking out.
"It's going to take a lot for this rift to be healed," royal biographer Penny Junor has said.
"The initiative has to come from Harry, and it doesn't seem to me that he is in any mood to do so."
This weekend, for the first time, there is a permanent monument to Diana in the grounds of her former home, a reflection of the fact that even decades after her death she continues to cast a very long shadow over the royal family.
Like it or not for the palace, in this regard, Harry and Meghan are already following in her footsteps.
• Daniela Elser is a royal expert and a writer with more than 15 years' experience working with a number of Australia's leading media titles.