Prince William sent a dramatic final-hour text to Prince Harry inviting him and wife Meghan Markle to Windsor Castle to view tributes the the late Queen and greet wellwishers.
It is reported that the Prince of Wales was not acting on orders of Prince Charles in setting up the surprise reunion with his estranged brother and sister-in-law on the walkabout at Windsor Castle on Saturday, as was previously thought.
William, the Princess of Wales, Harry and Meghan Markle - who were previously dubbed the 'Fab Four' - were reunited publicly for the first time since the Sussexes quit the UK and moved to the US as they were filmed shaking hands with the lined crowds and accepting bunches of flowers.
Dressed all in black, both couples looked slightly nervous as they arrived together in one car before spending about 40 minutes chatting to waiting fans outside the grounds of the castle.
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William and Kate were due to meet well-wishers and look at the floral tributes before William sent a text offering Meghan and Harry a last-minute invitation to join them, a source told the Daily Mail.
A source told the paper: "It happened very quickly – remarkable really considering they didn’t see each other in Scotland."
The paper reports that it was the Prince of Wales' decision to send his younger brother the olive branch of joining him for the walkabout, and it was "absolutely not the case" this was done on the direction of their dad, the new king, as was previously thought.
A royal source was said to have confirmed that it was the Prince of Wales' decision to send his younger brother the olive branch of joining him for the walkabout.
And suggestions William made the move after hearing Harry was planning to undertake his own walkabout with a film crew were "complete b******s", the paper was told.
It is thought the Prince of Wales had already mentioned the idea of viewing the flowers and greeting well wishers with Harry before reaching out to his younger sibling via text - something that was said to have been acknowledged by the Duke of Sussex.
It is thought William felt that a show of unity was key during a period of national mourning out of respect for their grandmother.
The insider added: "These coming days are going to be extremely intense and getting through them without distraction can only be a good thing."
The walkabout was originally scheduled for 4.30pm but was reportedly pushed back by 45 minutes as William and Harry discussed their plans.
The reunion of the two brothers and their wives came as a surprise considering their strained relationship since the Duke and Duchess of Sussex announced their intention to step back as royals just before the coronavirus pandemic.
And the relationship did not seem to improve following the events of Thursday in the hours before and after the Queen's death.
Harry is alleged to have pushed for his wife to join him on his journey up to Balmoral following the statement from Buckingham Palace regarding the concerning health of Her Majesty.
He ended up travelling alone, following news that Kate did not accompany William, while his brother was joined by Princes Andrew and Edward on the trip to Scotland.
The Duke of Sussex's private plane did not get to Aberdeenshire until a few hours after the Queen's death - he was reportedly told while en route from London.
However, he did not join his brother and father at the King's home of Birkhall on Thursday evening but instead chose to remain at Balmoral with the Duke of York, the Earl of Wessex and Princess Anne.
An insider said of the decision: "Two dinners were being hosted on the royal estate that night and there was a clear divide: One was for the new king and his heir, the other was for the rest of the family."
