Princess Diana's voice and performance coach Stewart Pearce believes that Prince Harry is writing a memoir to correct misconceptions about how he lived his life after his mother died 25 years ago.

The Duke of Sussex said his book, which comes out in December, will contain "accurate and wholly truthful accounts" of the "experiences, adventures, losses and life lessons" that have helped shape him. He wrote it not as the price he was born but as the man he has become.

Royal experts believe that he will share glimpses of his marriage and family life, and share the lessons he learned as a former working member of the royal family. His publisher, Penguin Random House, said it will give readers an "intimate" look into the royal's life.

Speaking about the memoir, Pearce lauded Prince Harry for his courage to share his story. He said the 37-year-old has a "fearless deserve for freedom" and likened him to Princess Diana, who had a desire to "speak her truth."

He said the reason why the Duke of Sussex is writing a memoir "is to correct a lot of erroneous stories about the nature of his life over the last 25 years since Diana's death."

Pearce told OK! magazine, "He is pregnant with the conviction of honesty and with leverage of transparency. He felt that he was very much a victim as he tried to steer his way forward being the freedom fighter and liberationist that he is; particularly in relation to Meghan Markle, who is very much a hallmark of the new American female."

The author of "Diana: The Voice of Change" lamented that Princess Diana would have done the same thing as Prince Harry had she been alive today. He said that "she would have written her autobiography full of all the many things she learned from her experiences within the Royal Family, and beyond."

He remembered that Princess Diana "loved to write personal correspondence, which for her added the personal touch, added love to the people she cared for." Pearce said that she would have waited for the right moment to release her memoir and align it with her charitable endeavors. Similarly, Prince Harry had announced that proceeds from the sale of his memoir will all go to charity, with Sentebale as the first recipient of $1.5 million.

Prince Harry
Britain's Prince Harry, a combat veteran who served two tours in Afghanistan, first attended the US Department of Defense Warrior Games in 2013 in Colorado Photo: GETTY IMAGES NORTH AMERICA / KEVIN WINTER