Prince William decided to put months of tension and upset with his brother Harry aside to show "unity" as they mourn their grandmother, a royal source has claimed.
The two brothers and their wives, the new Princess of Wales and Meghan Markle, were reunited publicly for the first time since the Sussexes quit the UK and moved to the US as they carried out a walkabout in Windsor.
William and Kate were due to meet well-wishers and look at floral tributes that have been laid outside the castle in the Queen's memory this afternoon, and offered Meghan and Harry a last minute invitation to join them.
Dressed all in black, the couples arrived together in one car before spending about 40 minutes chatting to waiting fans.
Speaking after the walkabout, a royal source said: "The Prince of Wales thought it was an important show of unity at an incredibly difficult time for the family."
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While the Sussexes' biographer Omid Scobie tweeted that William had made the decision "in the eleventh hour".
The Sussexes arrived holding hands as they walked alongside Kate and William. Meghan rubbed her husband's back reassuringly before linking arms with him as they looked at the flowers, while William pointed something out one particular tribute.
After looking at many of the tributes, all four walked off together and the two brothers got very close in heartwarming scenes.
The pair started talking to each other for a few seconds and gave each other support.
Then the two couples went off in separate directions and went to speak to people on different sides of the road, as is traditional for royal walkabouts.
All four royals took bunches of flowers to add to the sea of tributes and shook hands with people who had come out to meet them. Meghan shared a hug with one girl, who looked very emotional at their meeting.
Both Harry and William rushed to Balmoral on Thursday after doctors became concerned about the Queen's health, however neither made it in time to see her before she died. William travelled up with his uncles, Prince Andrew and Prince Edward, and his aunt Sophie Wessex.
Harry made the journey separately after returning to the UK from Germany where he was carrying out engagements for the Invictus Games. He left earlier than the rest of the family on Friday morning to catch a BA flight back to Heathrow.
The meeting comes after months of drama between the two couples, with Meghan and Harry making several accusations about the Cambridges in their Oprah Winfrey interview.
Meghan claimed Kate made her cry during the infamous bridesmaid dress fitting ahead of her royal wedding, while Harry said his brother was "trapped" in the royal system.
While the couples weren't seen interacting much during the outing, royal fans were still delighted to see the Fab Four back together, even though it was in such sad circumstances.
Nicola Standen, 44, from Witham, Essex said the Queen would be proud of her grandsons for coming out and greeting crowds and Windsor Castle together. She said: “That’s probably what she ultimately wanted. Nobody wants any upset in their family and you have to support each other at this time.
“I’m sure she’s looking down and is very proud of the brothers together. They’ve had such grief themselves so it’s good that they can support each other.”
Baljinder Ranow, 64, said it was “fabulous”, adding: “It was so beautiful to see.”
She said: “I felt so emotional and I felt the Queen would have loved it. I just hope in the future they remain like that and that the brothers come together, and the families.”
Tina Ward, 60, from Englefield Green in Surrey, echoed William's feelings. She said: "It’s really nice to see the family united in grief. It’s a shame it’s in grief but it’s nice that they’ve come together. I think it’s nice to see them all united here in town in which the Queen resided.
“I’m sure she would have been absolutely delighted. As a nan myself, I’d be absolutely delighted if my grandchildren had made up and were reunited.”
During the walkabout, Kate shared Prince Louis's heart-wrenching response to being told of his great-grandmother's death.
Banita Ranow, 28, heard Kate tell a group of children next to her: "Louis said at least Grannie is with great grandpa now."
She said Kate was "welling up" as she told the story.
