According to the Debrett's Guide To Etiquette and Modern Manners, money remains one of few "taboo topics" in polite conversation.
"Money, although an obsession with some, remains a private matter for many," the social bible decrees. Also off limits are ailments, sex, and "excessive gossiping".
Unfortunately, while public discussions about pounds and pence might be anathema to the upper crust, it's an issue that the Queen cannot escape right now.
After several months of seemingly doing little more than making a random appearance on Instagram with his ex-wife Sarah Ferguson Duchess of York, Prince Andrew is back in the headlines.
Over the weekend it was revealed that the Yorks are being sued in Switzerland for not making the final payment on the $31.5 million Swiss chalet that he and Fergie bought in 2014.
Per the Times, Andrew and Fergie had arranged to pay for the seven-bedroom home in the exclusive mountain enclave of Verbier in instalments and were due to pay the $12.5 million owing on New Year's Day this year.
The couple failed to front up the cash and now the unnamed owner of the chalet has filed papers with the Swiss debt collection office.
Andrew and Fergie, according to reports, had planned to put the property up for sale to pay off the debt but Covid-19 crisis has seen them struggle to attract interest.
Andrew's finances have long been a source of mystery and conjecture. While Prince Charles is the beneficiary of the Duchy of Cornwall, which is worth $1.8 billion and brought in $41 million in income last year, Her Majesty's other children must make do with far less.
Andrew, like his sister Princess Anne and brother Prince Edward, gets about $472,000 tax-free every year from his mum. The Prince also picks up $37,900 from his navy pension.
It's a tidy sum by all means, but is it enough to keep a man in $22,000 gold-plated Apple watches and $400,000 Bentleys?
He's not the only Windsor contending with having to pay their own way.
Harry and Meghan the Duke and Duchess of Sussex's Los Angeles digs have been made public, with it being revealed that the couple is living in actor and director Tyler Perry's $27 million Hollywood mansion.
After a tumultuous few months, the chance to stretch out next to the pool must be just the tonic the Sussex family needs.
However, despite all the vitamin D and privacy they are currently enjoying, the question of how exactly they too are going to support themselves in the future remains a thorny issue.
While combined, Harry and Meghan are said to be worth somewhere between $45 million and $60 million, their current lifestyle of private jets and Hollywood mega-mansions might be beyond their considerable means.
For example, Perry's house, should they want to rent it, would cost them $379,000-a-month, according to the Daily Mail, which comes to $4,548,000 annually.
That would constitute nearly all of the $4.7 million that Charles currently gives Harry and Meghan annually to fund their lifestyle, an arrangement that will be reassessed in 2021 (Charles gives the same amount of money to William and Kate).
This is before they have paid for the army of staff they would need, any private jet flights, and for their seven-figure cost of their security team. It is estimated this could all cost $20 million a year.
Pre-Covid crisis, there is every chance they could have pulled in the millions and millions they would need to fund this sort of lifestyle thanks to a few high-profile speaking gigs, book contracts and perhaps a stonking Netflix deal.
However, the Sussexes' economic reality, like hundreds of millions of other people, has starkly and profoundly changed.
US film and TV productions are still shuttered; the publishing industry buckling with slowing sales, literary festivals cancelled; and Wall Street is having conniptions.
With international conferences and billionaire confabs such as Sun Valley and Google Camp likely off the table for the time being, the chance of being the beneficiaries of some lovely six and seven figure speaking jobs is pretty much non-existent.
While their desire to support themselves is hugely admirable, the likelihood of them being able to make enough money to be fully independent given the parlous state of the world economy looks increasingly dicey.
While the circumstances surrounding Andrew and Harry's decisions to step back from royal duties are wildly different, they face similar financial uncertainty.
Here we have two men who were born a heartbeat away from the throne who, over the decades, have found themselves by virtue of the arrival of nephews and nieces being shunted further down the line of succession and thus further and further away from having access to sources of huge personal income.
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Both Andrew and Harry are clearly used to living certain sorts of lifestyles as befitting those of the son of a monarch (or future monarch), but don't quite have the resources to foot the bill that comes with it.
Just what is the Queen to do?
In the case of Andrew, she has already faced accusations of having been overly lenient towards him.
If she was to pay off this debt, it would be a public-relations nightmare and would most likely provoke widespread anger given the money could also go to helping the beleaguered British National Health Service. If she doesn't step in, she faces the embarrassment of her son being potentially dragged through the Swiss courts.
In Harry and Meghan's instance, there is a growing question mark over whether they will be able to earn the $20 million they will very roughly need annually to support themselves.
It seems unlikely Charles would cut them financially adrift, however, he faces having to walk a very delicate line given they upset millions in the UK when they stepped back from frontline duties and promptly moved to LA.
While Her Majesty and Prince Charles both face these ongoing pecuniary pickles, the bigger issue of one child of the sovereign getting a boatload of cash, and other royal children left to live on dramatically smaller pay cheques, is going nowhere.
One day, Prince George will take possession of the Duchy of Cornwall while Princess Charlotte and Prince Louis will have to make do with comparatively puny parental handouts.
There are no easy answers here, only the potential for an ongoing slew of PR crises, given there has always been significant public sensitivity around the royal family and how they spend money, a situation made even more precarious given both Andrew and Harry are no longer official working members of the royal family.
Sure, the Queen could cut a couple of cheques and sort out this current $32.5 million muddle ($12.5 million for Andrew and $20 million for Harry and Meghan) but that is far from a permanent fix – and would mightily anger her subjects.
However, nor can she let them flounder financially out in the big, cold world – that would just be a source of never-ending bad publicity.
The only sure thing here is that unless something drastic changes in how the royal family divvies up the regal spoils, then the question of funding the life of Princely "spares" will continue to wreak havoc for decades to come.
- Daniela Elser is a royal expert and writer with 15 years experience working with a number of Australia's leading media titles.