An episode in the recently released fourth season of “The Crown” is making at least one relative of the Royal Family hopping mad.

David Bowes-Lyon, whose father was first cousin of the Queen Mother, is publicly criticizing an episode about the Queen Mother’s nieces, Nerissa and Katherine Bowe-Lyon. In the episode, the mentally challenged sisters had been confined to a psychiatric institution for their entire lives.

While the family — including the Queen — had believed them to have died long ago, Princess Margaret (played by Helena Bonham Carter) discovers that they’re very much alive.

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Bowes-Lyon, however, is adamant that the way “The Crown” depicts that particular chapter in royal history is just plain wrong, and that all the royals knew of the existence of the sisters. 

Speaking with the Telegraph, Bowes-Lyon slams the episode as “fiction pretending to be fact,” insisting it has caused “frustration” within the family.

Bowes-Lyon’s comments echo those of British Culture Secretary Oliver Dowden, who said he’d be calling on Netflix to issue a disclaimer ahead of episodes of “The Crown” to remind viewers that what they’re watching is fictionalized drama that doesn’t always hew to actual fact.

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According to Bowes-Lyon, the episode’s plot is “complete fantasy.” In fact, he insisted Margaret had actually spoken about Nerissa and Katherine several times.

“She knew who they were in every respect,” he said. “It is completely wrong to say they were forgotten and certified as lunatics.”

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‘The Crown’ Season 4 Fact Vs Fiction