Prince Harry Will Open Up About Walking Behind Mom Princess Diana's Coffin in New Memoir

JEFF J. MITCHELL/AFP/Getty From left: Prince Philip, Prince William, Charles Spencer, Prince Harry and Prince Charles walk behind Princess Diana's casket at her 1997 funeral

Prince Harry's upcoming memoir will give insight into his experience walking behind his mother Princess Diana's coffin as a 12-year-old boy.

Spare, the Duke of Sussex's book that will be released on Jan. 10, 2023, is set to include the poignant day that the Princess of Wales was laid to rest. Prince Harry walked with his brother Prince William (who was 15), father then-Prince Charles, grandfather Prince Philip and uncle Charles, Earl Spencer through the streets of London during the 1997 funeral.

The book's publisher Penguin Random House said on the memoir's website, "It was one of the most searing images of the twentieth century: two young boys, two princes, walking behind their mother's coffin as the world watched in sorrow — and horror. As Diana, Princess of Wales, was laid to rest, billions wondered what the princes must be thinking and feeling — and how their lives would play out from that point on."

RELATED: Everything to Know About Prince Harry's Upcoming Memoir: 'I'm Writing This Not as the Prince'

Getty Prince William, Princess Diana and Prince Harry

Prince Harry, 38, previously recalled the emotional difficulty of walking behind his mother's coffin.

"My mother had just died, and I had to walk a long way behind her coffin, surrounded by thousands of people watching me while millions more did on television," he said in a 2017 interview with Newsweek. "I don't think any child should be asked to do that, under any circumstances. I don't think it would happen today."

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In the 2017 BBC documentary Diana, 7 Days, Harry said it was a "group decision" that led to the two brothers joining the procession.

"But before I knew it, I found myself with a suit on with a black tie and a white shirt, I think, and I was part of it," he said. "Genuinely, I don't have an opinion on whether that was right or wrong. I am glad I was part of it. Looking back on it now, I am very glad I was part of it."

Tom Wargacki/WireImage Princess Diana

In the same documentary, Prince William recalled it as a "long and lonely walk."

"It wasn't an easy decision, and it was a collective family decision to do that," the Prince of Wales, now 40, said. "It was one of the hardest things I've ever done. But we were overwhelmed by how many people turned out, it was just incredible. There was that balance between duty and family, and that's what we had to do."

Princess Diana's brother told PEOPLE and 2017's The Story of Diana that he didn't believe that "tiny" Harry should have made the grueling walk.

"I was just so worried — what a trauma for a little chap to walk behind his mum's body," Charles, 9th Earl Spencer, said. "It's just awful. And, actually, I tried to stop that happening, to be honest."

Credit: PENGUIN RANDOM HOUSE The book jacket of Prince Harry's memoir 'Spare'

Penguin Random House says of the Duke of Sussex's memoir, "For Harry, this is that story at last."

"With its raw, unflinching honesty, Spare is a landmark publication full of insight, revelation, self-examination and hard-won wisdom about the eternal power of love over grief," they added in the book description.

Prince Harry's author biography states he "is a husband, father, humanitarian, military veteran, mental wellness advocate, and environmentalist. He resides in Santa Barbara, California, with his family and three dogs." Harry and his wife Meghan Markle relocated to her home state in 2020 after stepping back as working members of the royal family. They have two children — son Archie Harrison, 3, and daughter Lilibet Diana, 1 — and three dogs — Guy, Pula and Mia.

Chris Jackson/Getty Images Prince Harry

Proceeds from the book and audiobook are expected to be donated to charity.

During an appearance at an August 2021 polo match benefiting Sentebale in Aspen, Colorado, the Duke of Sussex announced that he has committed $1.5 million of the proceeds from his forthcoming memoir to the charity. Harry co-founded Sentebale in 2006 with Prince Seeiso of Lesotho to help children affected by HIV in Africa.

"This is one of several donations I plan to make to charitable organizations, and I'm grateful to be able to give back in this way for the children and communities who gravely need it," he said in a statement.

According to the official website for Spare, Prince Harry will also give £300,000 to WellChild. He has been a patron of the organization that works to support seriously ill children and their families since 2007, and Meghan joined him at the annual awards in 2018 and 2019.

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"I'm writing this not as the prince I was born but as the man I have become," Prince Harry previously said in a statement. "I've worn many hats over the years, both literally and figuratively, and my hope is that in telling my story — the highs and lows, the mistakes, the lessons learned — I can help show that no matter where we come from, we have more in common than we think."

He continued, "I'm deeply grateful for the opportunity to share what I've learned over the course of my life so far and excited for people to read a firsthand account of my life that's accurate and wholly truthful."