Although Hanbury's name is only now just gaining traction and being linked to the royals thanks to rumors of an affair, she has long been a part of an elite social circle surrounding British royalty.
A former model married to the Marquess of Cholmondeley (pronounced Chumley), who is 23 years older than her, Hanbury has a well-established royal connection. Her grandmother, Lady Rose Lambert, was a bridesmaid in Queen Elizabeth II's marriage to Prince Philip, and her own connection with the royal family goes even deeper than that, Parade reports.
Hanbury and her husband are part of an elite crew known as the Turnip Toffs, a group of British aristocrats who live near one another in the countryside. The couple, who married in 2009, live at Houghton Hall, which was built in the 1700s for Britain's first Prime Minister, Sir Robert Walpole, and is located just a few miles away from the Cambridge's home, Amner Hall.
That close living proximity means that the Cambridge's and the Cholmondeley's have spent plenty of time together, with Flare reporting that the couples hunt together, throw garden parties, and host playdates with their children, as the Cholmondeley's also have three children. It has also been reported that Hanbury is Middleton's "close friend."
However, their friendly relationship seemingly hit a roadblock after Middleton and Hanbury had a falling out earlier this year, something that was first reported on in March and was quickly linked to long-standing rumors that the Duke of Cambridge has been unfaithful.
The rumors are so prominent that the British Royal Family has allegedly not only threatened legal action, forcing British tabloids to keep mum on the topic, but also attempted to shift focus away from the potentially crumbling relationship between the heir to the throne and his wife and instead to Prince Harry and Meghan Markle.
"In addition to being false and highly damaging, the publication of false speculation in respect of our client's private life also constitutes a breach of his privacy pursuant to Article 8 of the European Convention to Human Rights," attorneys with London law firm Harbottle and Lewis, which has represented the royal family before, said in a letter sent to at least one British tabloid, according to the Daily Beast.
Buckingham Palace has not yet publicly commented on the rumors, and despite the alleged affair, Prince William and Kate Middleton will be celebrating their 8-year-anniversary in May with a trip to north Wales.