Princess Diana shocked the nation when she sat down for a tell-all interview with journalist Martin Bashir on BBC Panorama in 1995. During the interview the Princess of Wales discussed the breakdown of her marriage to Prince Charles.
Writing in the Daily Mail, royal author Robert Lacey said the implications of the interview “struck young teenager William at an especially vulnerable moment”.
He claimed that Princess Diana did not consider the emotional effect the revelations would have on her eldest son.
Mr Lacey said Princess Diana only reflected on how it might impact her sons after the interview was over.
He wrote: “According to Simone Simmons, the Princess’s confidante and faith-healer, it took a phone call from William’s Eton housemaster, Dr Andrew Gailey, to prompt Diana.
“Gailey had read the advance publicity in the newspapers and phoned to tell her it was ‘imperative’, in his view, that she should come to explain things to William, face to face.”
According to Mr Lacey, Princess Diana told Prince William: “I’ve done an interview for TV.
“It’s going to air tomorrow night and I didn’t want it to catch you by surprise.”
When the interview was aired, Prince William sat alone to watch his mother reveal her and Prince Charles’ affairs.
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“And he knew his friends would poke fun at him, which they did.
“He felt she made a fool of herself — and of him.”
Prince Harry, however, is believed not to have watched the interview when it was first shown on TV.
Mr Lacey said it is unclear how Prince Harry later reacted to his mother’s interview revelations.
The royal author went on to explain how Prince William was in a “fragile place” when the Panorama interview was released.
Mr Lacey wrote: “He was only in his first weeks at Eton, having just endured the college’s then-notorious ‘welcome to the club’.”
Prince William was “furious” with his mother for mentioning her affair with James Hewitt and speaking badly of his father, according to Ms Simmons.
According to Mr Lacey, Princess Diana told Ms Simmons: “[Prince William] started shouting and crying and when she tried to put her arms around him, he shoved her away.”
The Duke of Cambridge later apologised to Princess Diana but she sensed that some “irretrievable damage” had been done, Mr Lacey wrote.
The author added: “This was the moment when William seems to have experienced that decisive act of detachment from the parent that marks the advent of adult life. The iron had entered his soul.”