King Charles and Queen Camilla are very much like a normal married couple, having marital troubles and arguments on a daily basis.

According to Camilla's sister, Annabel Elliot, the couple is "polar opposites" who often disagree about sleeping with the windows open.

In an excerpt obtained from Robert Hardman's book King Charles: New King. New Court. The Inside Story. it was revealed that this lighthearted dispute is a constant source of banter, with Charles usually getting his way.

Speaking of their ‘constant battle’ on keeping the windows open, the author mentioned Annabelle saying, "There's a constant battle about it," adding, "He will have opened it. She will creep in behind and shut it.”

“So there's a lot of: 'Oh, darling, you shut the window,' 'Yes, I have, because we're all freezing.' So a lot of banter goes on,” she continued.

Annabelle went on to add that the monarch "usually wins on that front," but the Queen Consort "wins most other things."

"The King dislikes being inside for too long and always has the windows wide open," she explained. "A meeting at Birkhall, his home in the Highlands, in the middle of winter was not for the faint-hearted."

"I can remember more than one occasion when I thought I might have actually got frostbite while trying to write with a hand I could no longer feel," she shared.