Prince Charles, 72, is thought to want to pare back the Firm when he inherits the throne from Queen Elizabeth II, 95. While the Queen has always maintained Prince Harry, 36, and Meghan Markle, 39, remain much-loved members of her family despite royal dramas, Charles could choose to do what his mother won't and strip them of their Duke and Duchess of Sussex titles and HRH styles.
What Charles will decide to do in regards to the Sussexes when he is king is a matter of speculation.
But according to a constitutional expert, he will have the power to make his son "plain Henry," in one fell swoop.
Discussing the future of Meghan and Harry's titles, academic Iain MacMarthanne told Express.co.uk: "As far as styles and titles are concerned the Queen is at liberty to strip whomever of whatever royal title and peerage.
"When Prince Charles inherits the throne he also inherits that same right."
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The expert added: "Accordingly, by a stroke, be it at the hand of Elizabeth II, or a future King Charles, HRH Prince Henry, Duke of Sussex, Earl of Dumbarton, and Baron Kilkeel, could quickly find himself becoming plain and ordinary Mr Henry Charles Albert David Mountbatten-Windsor."
Harry and Meghan have held onto their titles despite stepping down as senior royals last year but their recent commercial activities have prompted calls from critics for them to be stripped.
They have seemingly ignored their promise to the Queen to not use their royal status in connection with their work after Megxit and have continued to trade off their titles.
Meghan's children's book The Bench was published under "Meghan, Duchess of Sussex" while a recent press release about Harry's upcoming memoir also referred to him as the Duke of Sussex.
Not only have the couple used their royal status to their own benefit but they have done so while firing shots at the institution.
In their March interview with Oprah Winfrey, the Sussexes savaged the Firm and made damning allegations against the royal household, including one of racism.
But despite their attacks, which the Queen said would be dealt with by the family in private, they continue to employ their Duke and Duchess of Sussex titles.
Charles may choose to leave Harry's title intact because of the lasting memory of Princess Diana being stripped of her royal status following their divorce.
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Mr MacMarthanne added: "One thing can however be kept in mind, the formal removal of the HRH from Diana, Princess of Wales, after her divorce, was seen as a petty, spiteful act and not one that would actively be sought to be repeated."
Harry has kept his place as sixth in line to the throne and cannot be removed from the line of succession without an Act of Parliament, Mr MacMarthanne explained.
He added: "On the question of removing Prince Harry and his heirs from the line of succession, only Parliament, through an Act of Parliament, can alter the succession as it is presently laid down in law.
"Neither the Queen nor a future King Charles would have a part to play in this other than having to give Royal Assent at the end of the process."
Touching on the future king's reported wish for a slimmed-down monarchy, Mr MacMarthanne said: "Prince Charles has reputedly long desired to have a slimmed-down monarchy, ensuring that it is not a financial burden on the state, and freeing those not in direct succession to have a private life.
"To this end, it is supposed that working royals would be limited to the monarch, their spouse, the heir and their family.
"All other members of the family would then be free to pursue a private life following their own careers and interests.
"Originally Prince Harry was believed to have featured in Prince Charles’s plans prior to his retirement from being a working royal."