Andrew Morton, Princess Diana’s biographer, on royal book writing

Andrew Morton, Princess Diana’s biographer, has revealed the shocking question he never asked.

The late royal was famously interviewed for his 1992 book Diana: Her True Story – In Her Own Words, published the same year the mother-of-two officially separated from her husband Prince Charles.

Hello! magazine’s A Right Royal PodcastMorton shared his thoughts on the writing process for the best-seller.

In case she was prompted to pull out, this included the surprising thing that the journalist, now 70 years old, omitted to say to her.

He stated that the only question I had never asked her was “Why are you doing this?” He said: “The one question I never asked her was, ‘Why are you doing this?'”

Morton maintained that the princess had never regretted speaking to him for his book and was always relieved to have shared her experiences.

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This in mind, he suggested to Prince Harry, 38 (whose memoir Spare launched earlier this week) that he would always be thankful he shared his tale.

The book by the Duke of Sussex, which sold over 1.4 million copies in its first day, has been the subject of a lot of controversy.

Morton shared that Harry’s mother, who died in 1997, was moved by the book she had just read.

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He said: “I remember occasions when Diana was in tears talking about some of the issues in her life, mostly her suicide attempts – and when I sent her to read through chapter six, she was in tears reading it because it just brought back so many memories.

“She did have a difficult childhood, an unhappy childhood, and talking about that as well it was like ploughing a field – it brought to the surface all kinds of unhappiness.”

Watch: Prince Harry comes under increasing criticism after his memoir revelations