King Charles III discovered his mother was dying in a frantic phone call, after which “everything was silent”.
Queen Consort Camilla was about to be interviewed by former US President George Bush's daughter when an aide was heard running in the corridor outside.
Minutes after taking the call, she and the then Prince of Wales were aboard a helicopter flying towards Balmoral.
The call was taken at 12.30pm on September 8 - around the same time the world was told of the Queen’s ailing health.
Newsweek’s Chief Royal Correspondent Jack Royston told True Royalty TV’s The Royal Beat: “Charles and Camilla were in Dumfries House.
"Camilla was actually about to record an interview with Jenna Bush Hager, who said she heard footsteps running in the hallway.
“Charles took a call, everything was silent, and they were asked to be silent.
“Then the next thing she knew, Charles and Camilla were in a helicopter. And that was at 12.30 [on Thursday 8th September], so that was around exactly the same time that we were told.
“So they didn’t wait, they didn’t give Charles an hour or two hours [before telling the public].”
During the programme, guests also discussed the feuding brothers William and Harry, as well as the King’s first address to the nation the day after the Queen’s death.
Mr Royston added: “I see in Charles a bit of George V - the sort of avuncular, fatherly figure of the nation. And it’s benefited him, his older years.”
Discussing the new Prince of Wales’ relationship with his brother the Duke of Sussex, Historian Tessa Dunlop said: “[William and Kate] realise their positions are a privilege, that they are honoured, they are lucky … and that has bred in William a magnanimity towards his brother.
“I think it was generous and it was right for him to stretch out an invitation to Harry [to join him and Kate on the Windsor walkabout].”
Royal commentator Wesley Kerr added: “I think it’s very much a moment [for the Waleses and the Sussexes] to heal.
“It may not be a permanent repair because we still don’t know what’s going to happen with Harry’s book, which apparently is finished.
“So what’s the deal with the publishers if it says harsh things about people? So that’s unresolved.
“I should think that Meghan’s podcasts will tone down.”
Overnight Bush Hager - the daughter of ex President George W Bush - told the Morning Show she had dined with King Charles the night before his mother's death.
The journalist had flown to Scotland to record an interview with Camilla, Fox News reported.
Around two hours before their chat however she and the team heard aides running up and down the corridors of Dumfries House as they were setting up.
She said: "They said he’s on a call can you please be quiet.
"They said the Queen is ill and they’ve gone and rushed off to be with her.
"We just said our hearts are with them."
Thousands of people have continued to queue overnight to see the Queen lying in state in Westminster House along London’s South Bank.
Full details of the Queen’s funeral were released yesterday, with her majesty set to be laid to rest alongside her beloved husband, the Duke of Edinburgh.
