Given that Prince Charles and Camilla, Duchess of Cornwall were once Britain's most polarising couple due to their reputation-shredding affair, the fact that they managed to win over the public following their marriage has been miraculous.
There was barely a peep of protest when Her Majesty announced earlier this year that Camilla had her support to become Charles' Queen Consort when the time came. Sadly, that appears to have all changed this week!
Upon the Queen's declaration, a PR offensive from Clarence House was launched, which has seen the duchess, 75, splashed across English magazines in a bid to guarantee her place at the top.
But just as she and Charles were toasting a job well done, a bombshell new allegation has brought the couple to their knees – throwing doubt over Charles as king, and more so, Camilla's place in the firm.
Last year, Charles' son Prince Harry and daughter-in-law Meghan, Duchess of Sussex claimed that an unnamed member of the royal family had made racist claims about their then unborn first child.
In an explosive new book, Revenge, author Tom Bower alleges that the so-called "royal racist" was in fact Camilla.
He claims that when Harry, 37, and Meghan, who turns 41 this week, began dating in 2016, Camilla quipped to the prince, "Wouldn't it be funny if your child had ginger afro hair?"
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Tom reports that Harry first reacted with a chuckle, but after repeating the conversation to Meghan, his laughter turned to utter fury.
Since the damning claims surfaced, palace insiders have been in overdrive to save Camilla's reputation for the second time and rushed to deny the story.
While some palace insiders have since insisted Camilla is not "the racist", one thing is clear – despite their best efforts to defend Camilla, it hasn't been good for her reputation.
It's a situation that has left Charles, 73, "worried" say insiders, who reveal the future king can't help but blame Camilla for being so naive when it comes to the Sussexes.
"Charles just feels Camilla should be more careful, particularly when so much is at stake," explains a source, who notes the situation has not sat well with the heir.
"This has undone 20 years of hard work from Camilla and Charles, who managed to turn her into an acceptable future queen."
"He is perhaps more upset than Camilla," adds the insider, who says he can't help but think that Tom's claims will derail any chance of a publicly approved takeover of the monarchy.
"He knows he's not popular with the younger generation of Brits and is frankly quite upset that Camilla could have ever comprised his position.
"A racism scandal involving Camilla is the last thing they needed – Charles fears it will put his accession in jeopardy if it gets any further out of hand."