Meghan Markle and Prince Harry will split from the charity they run with the Duke and Duchess of Cambridge, sources have claimed.
The brothers set up the Royal Foundation in 2009 and Kate joined two years later after marrying William, and she has been a key part of its work since.
Meghan joined after marrying Harry last year, but now it has been claimed that the Sussexes will go their own way and focus on their own charities separately.
The royals were nicknamed the Fab Four when they took to the stage for a Q&A about the charity in spring last year, in what was meant to become an annual event.
A source told the Sun: "The couples have been given two options – the first is to leave things as they are and the second a complete split.
"Nothing has been formally ratified but all the mood music is suggesting the Sussexes will break away.
"Nothing will be done quickly and it’ll be a phased untangling of many of the joint initiatives, not an overnight chop."
While the royals will continue to work on some projects together, reports claim it will be a "major blow" for the charity as it won't have the star power of all four of them together.
The source also claimed that while the Sussexes weren't in any rush to make changes, the Cambridges are.
The couples have already split households, with Meghan and Harry setting up their own office in Buckingham Palace.
In March charity announced it was "reviewing the charitable structures".
Speaking this morning, a spokesperson for the charity said they will not pre-judge the recommendations.
A statement released in May said: "The Duke and Duchess of Cambridge and The Duke and Duchess of Sussex are committed to the work they are carrying out through The Royal Foundation and are proud of what they have achieved together.
"The work to prepare both couples for their future roles will of course have implications for how they manage their charitable and philanthropic activity into the future.
"As part of this, a review of how they conduct their charitable activity will be undertaken. This will include reviewing the structure of The Foundation to ensure that Their Royal Highnesses have the best possible charitable structures in place for the future."
The Royal Foundation's board next meets on June 19, where the split is expected to be confirmed.
The couples recently launched Shout - a crisis text line - but it was set up independently rather than through the foundation.
The news comes after reports that Harry and William didn't see each other personally for six months after the Royal Wedding, despite living just a few doors down from each other.
A charity source said they had "believed in them as the power of four", but said it was "very sad" that it was going to end.
The Foundation was set up to focus on four areas which they are particularly passionate about - mental health, conservation, young people and the Armed Forces.
Over the years it has worked on a number of projects including Heads Together and the launch of the Invictus Games.