The one sentence in King Frederik's memoir that speaks volumes about his marriage.

King Frederik of Denmark has given us a rare glimpse into what life is like with his wife Queen Mary behind closed doors. 

The monarch, who was appointed to the throne earlier this month following Queen Margrethe II's abdication, opened up about his immensely private relationship with the Australian-born royal in his new surprise memoir, Kongeord.

In an excerpt from the book, the King admitted Queen Mary has taught him he is "not always right" just because of his gender. 

He also said she calls him out on what he learned from his "patriarchal" father.

Watch: Opening Day - Crown Princess Mary Of Denmark. Post continues below.

"I have learned a lot from having a wife who from time to time reminds me that I am of course not always right and that my words are not reliable per se, just because I'm the man of the house," he said.

"Although I can sometimes catch myself thinking, 'Oh, do we really need five more minutes of discussion?', I accept that Mary would like to turn over a few more stones and then we'll take five or ten minutes more."

The 110-page-long memoir, which translates to The King's Word in English, was co-authored by Jens Andersen and unveiled the King's plans for the future. 

But it's Frederik's comments about his wife that have fascinated fans of the royal couple, including a short sentence that seemingly references his alleged "affair" with Mexican socialite Genoveva Casanova after they were photographed on a night out together in Madrid in November 2023.

"I love marriage, my wife, our children and the whole happy base that arises for the people who manage to stay together and persevere," he wrote. 

The royal also referred to Queen Mary as his "partner" and "wing-woman" in the book and shared what his mother said on their wedding day.

"I remember how my mother, Queen Margrethe, said in her wedding speech in 2004 that I had found peace and joy with Mary," he said. 

A then-Mary Donaldson met the Danish royal at a pub during the 2000 Sydney Olympics. The pair will celebrate 20 years of marriage on May 14. 

Read more: On September 16, 2000, Mary Donaldson walked into a Sydney bar...

Feature Image: Getty.

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