Prince Harry and Prince William may have to put another united front in public when they attend Queen Elizabeth II's Platinum Jubilee celebrations in June.

Royal watchers are already wondering what the atmosphere will be like when the Duke of Sussex reunites with his father, Prince Charles, and his brother, the Duke of Cambridge, for the four-day celebration. A royal expert claimed that the trio may have to put their differences aside for the sake of Queen Elizabeth II.

Katie Nicholl told Birmingham Mail that "Harry will want to be a part of the celebratory weekend, and will almost certainly be required to appear with William at that time." She added that the brothers "will have to make concessions" and that the Platinum Jubilee celebrations "should give them more of a chance to thrash it out."

Meanwhile, others are already anticipating an awkward reunion. It is believed that Prince Harry's interest to be there for the event has caused problems for palace aides. They are debating what his role would be during the celebrations and where he should be standing on the Buckingham Palace balcony during the Trooping the Colour parade.

Royal astrologer Debbie Frank even suggested that there will be communication struggles between family members during the Platinum Jubilee celebrations. The Duke of Sussex would feel "awkward and out of step."

However, it is believed that the 37-year old is already on "much better terms and have been having friendly chats and video calls" with his father. Prince Charles reportedly made the effort first to mend his alleged rift with his son and has had "good-natured and enjoyable video calls" with him, Meghan Markle, and their children, Archie and Lilibet in the past few months.

As for Prince William, he and Prince Harry appeared to be on friendly terms when they both attended the unveiling of Princess Diana's statue at Kensington Palace in July last year. They smiled and chatted with each other, although it was said to be a united front for the paparazzi's sake. Nicholl said the brothers will have to "compromise" if they do not want to court drama during the Jubilee Platinum celebrations.

Meghan Markle, Prince Harry and Prince William
Prince Harry last year revealed that he had grown apart from his older brother William Photo: AFP / Tolga AKMEN