The real royal scandal may have nothing to do with the American Duchess of Sussex — but with a story about Kate and Prince William. Until this week, mainstream publications in both the U.K. and the United States had been reluctant to pick up on the story.

It involves the unsubstantiated but persistent and “sensational rumor that has electrified British high society for almost a year,” the Daily Beast reported Tuesday.

The rumor is that William may have become too friendly — or even had an affair — with an aristocratic neighbor while his wife was pregnant with their third child, the Daily Beast added.

Recent reports state that the Duke of Cambridge has cheated on Kate Middleton. He supposedly had an affair with Rose Hanbury, who happens to be a friend of his wife.

The Sun reported, the Duchess of Cambridge had become best friends with Rose Cholmondeley, a former model who also is in her mid-30s, who also has young children and who is married to David Rock­savage, a man 23 years her senior. Rocksavage also is known as the Marquess of Cholmondeley and comes from an old aristocratic family.

But Kate, for some reason, told William that Rose needs to be “phased out” as one of the couple’s close friends. A source told The Sun: “It is well known that Kate and Rose have had a terrible falling out. They used to be close but that is not the case any more.”

That was it for the Sun story — that Kate had a falling out with a friend, without saying why. The story might have died there because, as Slate’s Ruth Graham wrote, who cares about a “tiff between two toffs?”

But two days later, the Daily Mail’s royal correspondent Richard Kay went to great lengths to rebut The Sun report. Kay quoted royal sources as saying that the two couples were never that close, though they are apparently close enough to laugh off The Sun report.

After that, writer Nicole Cliffe posted a Twitter thread in which she presented the theory that Prince William cheated on Kate, and that was the source of the tension between him and Prince Harry — not, as was previously reported, Meghan Markle.