To borrow the words of William Shakespeare, "something is rotten" in the House of Windsor.
Two months after their rift went public, Kate Middleton and her 'rural rival' Rose Hanbury crossed paths for the first time at the Queen's state banquet for President Donald Trump at Buckingham Palace last week.
WATCH this video to get a glimpse inside the glittering gala dinner:
While the Duchess of Cambridge was reportedly shaken by the presence of her former friend, the biggest surprise came when royal fans noticed that the Marchioness of Cholmondeley wasn't wearing her wedding ring.
Rose, 35, has been married to 58-year-old David Rocksavage, 7th Marquess of Cholmondeley and Lord Great Chamberlain, since 2009.
Rose's husband David also attended the gala for President Trump, but the willowy former model made a subtle statement in her white gown by foregoing the wedding band she usually wears.
The couple arrived separately and were not photographed together during the evening in London, Express.co.uk reports.
The Cholmondeleys live minutes from Prince William and Kate's Norfolk bolthole Anmer Hall in their own equally lavish mansion Houghton Hall, while the Cambridge children - Prince George, Princess Charlotte and Prince Louis - have been playmates of Rose and David's kids, twin sons Alexander and Oliver and daughter Lady Iris, for years.
Earlier this year, The Sun broke the story that William and Kate had "fallen out" with their high-society friends for an unknown reason, prompting Kate to order her husband to banish Rose from their suitably named social circle 'The Turnip Toffs' for good.
"No one understands quite how things have come to this. Over the years, Rose and Kate's lives have been entwined in many ways," a source told The Sun in March.
"It's well known that Kate and her former best friend Rose Hanbury have had a terrible falling out. They used to be close but that is not the case anymore."
So ruffled was the House of Windsor by the rumours, Prince William made the unusual move of threatening legal action against publishers.
The falling out is all the more intriguing given Rose and David's historic connection to the royal family.
Rose's grandmother, Lady Elizabeth Longman, was a bridesmaid at Queen Elizabeth and Prince Philip's royal wedding in 1947.
Her Majesty remained close with Ms Longman until her death in 2016.
Rose was also invited to William and Kate's 2011 wedding at Westminster Abbey, and the Cambridges were the star guests at a charity function held by the Cholmondeleys at Houghton Hall three years ago.