Prince William and Prince Harry are embroiled in “one of the most public royal rifts that has ever been”, but that could all change very soon.

The Duke of Sussex stepped down from the Royal Family four years ago and has since made a number of shocking allegations about his brother. The two haven’t been seen together in years, but royal expert Richard Fitzwilliams believes they could reunite after King Charles and Princess Kate were both diagnosed with cancer.

Harry is set to return to the UK in May to celebrate the 10th anniversary of the Invictus Games and Richard believes royal fans could be in for a surprise reunion between Harry and William. “Serious illness is the big changer, despite everything that’s happened, given the seriousness of the situation, anything can happen,” he said.

Richard said William is “under tremendous pressure” at the minute, adding how serious illness can be a “game changer”. Speaking to The Sun, he continued: “There could be something that surprises us all. You could have all the Sussexes over here, it’s perfectly possible a reunion could happen. Next week, next month, next year, you could get something you never dreamed you’d get.”

However, the expert did point out how the brothers have a “very deep rift”, which is unlikely to be fixed overnight. Harry and William’s relationship has worsened over the years after the Sussexes made a number of accusations against the Royal Family in their Netflix docuseries.

Harry also hit out at Prince William and Princess Kate in his memoir. In the book, the Duke of Sussex opened up about an explosive row he had with William, during which the Prince of Wales allegedly called Harry’s wife Meghan “difficult”, “rude” and “abrasive”. Harry claims his brother then “grabbed me by the collar, ripping my necklace, and he knocked me to the floor

Harry is set to return to the UK in a matter of weeks. He’s due to speak at a special service to celebrate the Invictus Games, which will be held at St. Paul’s Cathedral on May 8.

It’s believed the Prince and Princess of Wales have tried to encourage Harry and Meghan to bring their children with them to the UK to end the royal rift. Royal author Tom Quinn previously told The Mirror: “There is no way Meghan would bring the children to the UK. William and Kate have suggested that Meghan and Harry bring the children and that the two couples and their families try to make up, but the suggestion is not leading anywhere so far.”

Harry recently opened up about his plans to return to the UK. During an appearance on Good Morning America, he said: “So my family and my life in California is as it is. I have got other trips planned. That would take me through the UK or back to the UK, so you know, I’ll stop in and see my family as much as I can