Queen Camilla has reportedly urged King Charles to "slow down".
The 75-year-old monarch is set to undergo a "corrective procedure" for an enlarged prostate, and his wife has already encouraged him to take things easy.
An insider told The Sun newspaper: "The Queen has told him he needs to slow down a bit."
Charles was recently spotted driving around Sandringham estate, where he is supposed to be resting ahead of his operation.
The monarch ascended to the throne in September 2022, following the death of Queen Elizabeth, and he's been typically diligent in his approach to the role ever since.
The insider added: "His work ethic is well known and not a surprise to anyone."
Meanwhile, a royal expert recently claimed that Charles' health troubles underline why "you don’t want a slimmed-down monarchy".
Richard Fitzwilliams told Us Weekly: "It shows you don’t want a ‘slimmed down’ monarchy. Only four [people] are under 70 as it is."
The monarch has made a concerted effort to reduce the number of senior working royals since he ascended the throne, but Richard warned that the policy comes with some potential pitfalls.
He added: "[Prince William] is a Counsellor of State, who, in theory, could stand in for the monarch in the event of him being abroad or of incapacity.
"If necessary, Counsellors of State could step in for the monarch. There are several, including [Prince] Harry and [Prince] Andrew, who obviously would not be asked to."
Meanwhile, the Princess of Wales recently underwent abdominal surgery and she's not expected to resume public duties until after Easter.
The 42-year-old royal - who has Prince George, ten, Princess Charlotte, eight, and Prince Louis, five, with her husband - also asked for her medical information to remain private.
A statement from the palace said: "The Princess of Wales appreciates the interest this statement will generate. She hopes that the public will understand her desire to maintain as much normality for her children as possible, and her wish that her personal medical information remains private.
"Kensington Palace will, therefore, only provide updates on Her Royal Highness’s progress when there is significant new information to share."