Prince William has been left concerned for the wellbeing of the Duke and Duchess of Sussex, it is claimed, after the couple told a television audience of millions of their personal unhappiness and a rift in the Royal Family.
The Duke is said to be "worried" about his younger brother, who on Sunday night publicly confirmed the siblings are on "different paths" and spending less time together.
A palace source told the BBC of household fears the Sussexes are in a "fragile place", with Prince William hoping they "are alright" after Prince Harry unexpectedly laid bare details of their private relationship in a television documentary.
Acknowledging a "rift" in conversation with friend and broadcaster Tom Bradby on ITV, Prince Harry admitted "inevitably stuff happens" under the pressure of royal life.
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His decision to speak about the brothers' relationship immediately placed them at the centre of a worldwide conversation, detailed on the front page of five leading British newspapers and headline news on radio and television from the Today programme to Loose Women.
The documentary screens on TVNZ on Labour Day Monday.
The decision left insiders baffled and led royal experts to question his wisdom, suggesting the Queen would be concerned and "a little bit dismayed" by how the Sussexes lives were unfolding in front of the cameras.
The Dukes of Cambridge and Sussex are understood to have been in contact in person, while a Buckingham Palace spokesman declined to confirm or comment on any potential private conversations the Queen has had with her grandson.
A spokesman for Kensington Palace, the offices of the Cambridges, declined to comment.
But, asked by the BBC, a source downplayed suggestions that the Duke of Cambridge was angered by his brothers words, saying he was instead concerned for the Sussexes.
The brothers, who were once inseparable in the public imagination thanks to the unique bond they formed after the death of their mother, have suffered a significant parting of ways in the last year, splitting their charitable foundation.
Asked about a "rift" with his brother during an ITV documentary, Prince Harry laughed and said: "We are certainly on different paths at the moment but I will always be there for him as I know he will always be there for me.
"We don't see each other as much as we used to because we are so busy but I love him dearly.
"The majority of the stuff is created out of nothing but as brothers, you know, you have good days, you have bad days."
He also spoke of needing to constantly manage his mental health issues thanks to living in the public eye.
Those close to him today praised the answer as both truthful and tactful, painting the brothers as a normal family.
Others considered it an unforced PR error not to deny the spat or politely decline to answer the question from Bradby, a friend of both brothers for many years.
Doco screens to huge audience, leads five newspapers
Prince Harry's candid disclosure was watched by an average audience of 2.8 million people and a peak of 3.2m, as it was broadcast on ITV with select clips being shared around the world online.
Significantly, the documentary will also screen on ABC on Wednesday night to the Duchess's home country of America, where the narrative that she is facing relentless sexist and racist hostility in Britain has taken hold on breakfast and chat shows.
On Monday, it reached the front page of five leading British newspapers and became the headline news on radio and television from the Today programme to Loose Women.
The disclosure will leave palace aides struggling to deny further revelations about the brothers, after repeatedly insisting the split of their Royal Foundation this year was purely down to the natural "divergence" of their working lives.
The Sussexes are to take an extended period of leave from mid-November onwards.
A spokesman for Buckingham Palace would not comment on whether the Queen had encouraged or approved the idea, or whether anyone outside the Sussexes' close-knit team of confidentes were aware of it.
Jonny Dymond, BBC royal correspondent, said the documentary showed the Duke and Duchess are "clearly having a terrible time", but noted that the monarchy is supposed to be a unifying force in the United Kingdom.
"Suing the biggest selling newspapers in the country, setting off and taking part in public spats with other parts of the royal family, airing stories that they might go abroad?" he told Radio 5 Live.
"If they're doing that they're really not unifying anything. This is already a divided country and this is not doing the job.
"And that, the Queen will be concerned about."
Author Penny Junor said the Queen would be "a little bit dismayed", while Phil Dampier added: "There's no doubt the Queen and other royals are very worried about the direction Harry and Meghan are taking and it's very serious."