Prince William Was 'Close' to Not Inviting Prince Harry to Windsor Walkabout: 'It Was All Led by' King Charles

'Endgame' author Omid Scobie shares the brief notice Prince Harry and Meghan Markle received about the public outing after Queen Elizabeth's death

Prince William, Kate Middleton, Prince Harry and Meghan Markle’s united appearance after Queen Elizabeth’s death almost didn’t happen, Omid Scobie writes in Endgame.

In the book, published on Tuesday and originally excerpted in PEOPLE, Scobie writes that King Charles nudged Prince William to invite the Duke and Duchess of Sussex to view tributes and greet the public with him and Princess Kate after Queen Elizabeth died in Sept. 2022.

"Essentially, he told William to swallow his pride and invite his brother and sister-in-law to join them when they greeted mourners and well-wishers in Windsor that day. William wasn’t keen. This was his moment with the public, but the King put pressure on [him],” Scobie quotes a palace source as saying in Endgame.

According to the book, shortly before the outing, Prince William “sent his first text message in months to Harry, suggesting it would be ‘good’ if they came along, too.”

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Speaking exclusively to PEOPLE surrounding the release of Endgame, which chronicles both the breakdown of the royal family and the weakening of the modern monarchy, Scobie stresses that the "Windsor Walkabout" was King Charles’ idea.

The author adds that a source "said it was all led by their father, that he was the one that made the suggestion."

Commenting on the significance of the appearance, which marked the first time that the couples had appeared together in years, "It showed that all four are capable of switching it on and doing what’s right in the moment," Scobie says.

Related: Kate Middleton Was 'Uninterested' in 'Forming Bond' with Meghan Markle, New Book Claims

“I thought potentially that could open doors to other moments of seeing what matters and putting certain things to one side, just to coexist or to find some sort of common ground,” he tells PEOPLE. “But I think the thing that surprised me the most was that afterward everyone just went their own ways and nothing happened beyond that.”

Scobie also decodes the brief notice Harry and Meghan had for the public moment as a sign of William’s indifference.

“The fact that it was about to go ahead without the Sussexes, who were only asked 40 minutes beforehand, shows just how close William was to not doing it at all. And if it wasn't for Charles, it wouldn't have [happened],” Scobie says.

Kensington Palace had said that Prince William invited his brother and sister-in-law to join them. The Prince of Wales thought the walkabout to greet the crowds "was an important show of unity at an incredibly difficult time for the family," a royal source told PEOPLE at the time.

However, a friend of Kate's told PEOPLE that it was her idea. "She didn't want her or William to have any regrets," the friend said.

The Duke and Duchess of Sussex were in Europe for a series of charitable events in when Harry’s grandmother died at age 96. The couple, who relocated to Meghan’s home state of California in 2020, extended the trip to attend the funeral events.

While relations remained strained between Prince Harry and Meghan and some other members of the royal family following the U.S. move, Scobie writes that the Sussexes wanted to do the right thing after Queen Elizabeth’s death and quickly readied for the appearance in Windsor.

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The foursome took an emotional tour of the tributes honoring Queen Elizabeth and connected with well-wishers at Windsor Castle for about 40 minutes. In Endgame, Scobie writes that Prince William “orchestrated a somewhat forced photo” of the group together and recapped that newspapers later credited the heir to the throne as behind the united front, which he says both Buckingham Palace and Sussex sources have denied.

The foursome later left in the same car, and reports later emerged that both couples found the outing difficult.

While Robert Jobson wrote in his book Our King: Charles III that Kate later said the outing was "one of the hardest things she's ever had to do," a source told PEOPLE that Meghan felt similarly about the walkabout.

"That's the longest they had ever been away from the kids, and then on top of it, knowing what's being said out there — it was very difficult," the source said.

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Read the original article on People.