Princess Diana wanted to share with the public her journey towards becoming a more confident person with the guidance of her voice and presence coach Stewart Pearce, but not until both of her sons got married.

In a recent conversation with Us Weekly about his upcoming book "Diana The Voice of Change," Pearce revealed that he waited this long to release the book because Diana had asked him not to do it until Prince William and Prince Harry have settled in their personal lives. The author recalled: "Diana said to me shortly before she died, 'Wouldn't it be amazing if all of the work that we've done together became a book, but if you do, please don't publish it until after the boys are married.'"

Stewart believes that it was because Diana wanted her sons to be stable in the love that she wanted for them with their chosen bride. "That was the meaning that I put to it — that it was to do with a level of that they could begin to then reflect through their wives on the possibility of all of the exercises that I include within the book," the author explained.

The voice coach added that the Princess of Wales was "literally waiting" for her sons to "move into that level of emotional resonance themselves, where there was a level of emotional intelligence that they could review her life from and therefore see her not as a weak vessel, but to see her as being the brilliant, sensitive and intensely excavated woman that she was."

Princess Diana died in a car crash in Paris in August 1997, when she was 36, while William and Harry were 15 and 12, respectively. William married Kate Middleton in 2011, at the age of 28, and shares three children with her- Prince George, 7, Princess Charlotte, 6, and Prince Louis, 3. Harry tied the knot with Meghan Markle in 2018, at the age of 33, and welcomed their son Archie the next year. The couple is also expecting their second child, a baby girl, in a few weeks.

In addition to the fact that Diana's condition is now fulfilled, Stewart felt now would be the right time to release the book because of "all the things that are going on with Harry and Meghan." He said: "I thought it was really important to step forward and say, 'OK, well, their mother was one of the first great voices of change.' And now Meghan is becoming another great voice of change and [here's] how we can support them and how we can support [all women] in this endeavor."

Princess Diana
4 October 1985: Diana, Princess of Wales with her sons, Prince William and Prince Harry, at the piano in Kensington Palace Tim Graham/Getty Images