Through The Lens: Princess Diana's Life In Photos
The Duke of Cambridge and Prince Harry are still living with the devastating emotional impact of their mother's death.
The royal brothers chose the 20th anniversary year of the car crash that killed Diana, Princess of Wales to begin talking candidly about how they are still grieving.
The backdrop to the year has been William, Kate and Harry's mental health campaign, Heads Together, which has encouraged people to speak about their problems or be a sympathetic ear for others in need.
And it appears they have followed their own advice and talked openly about losing a parent and the psychological issues that can follow.
William was 15 years old and Harry just 12 when their mother Diana, 36, her lover Dodi Fayed, 42, and their chauffeur Henri Paul were killed when their Mercedes crashed in the Pont de l'Alma tunnel in Paris on August 31 1997.
Days later images of the young princes walking behind the horse-drawn gun carriage transporting their mother's coffin through the streets of London were etched in the public's memory.
But the Duke and Prince appear to have dealt very differently with the emotional fallout following their bereavement, with William seemingly coping better with his feelings of "anger" while younger sibling Harry admitting to receiving professional help.
In an interview with Newsweek magazine, Harry voiced his disapproval at having to walk behind Diana's funeral cortege watched by thousands with his older brother, his father the Prince of Wales, grandfather Duke of Edinburgh and his uncle Earl Spencer.
Today The Duke of Cambridge and Prince Harry will pay tribute to their mother Diana, Princess of Wales. pic.twitter.com/zkfhfPxcsY— Kensington Palace (@KensingtonRoyal) August 30, 2017
With The Duchess, they will visit The Sunken Garden which has been transformed into a special White Garden dedicated to The Princess pic.twitter.com/AFt523XPV3— Kensington Palace (@KensingtonRoyal) August 30, 2017
Harry said: "I don't think any child should be asked to do that, under any circumstances. I don't think it would happen today."
Diana's brother Charles, Earl Spencer, has claimed he was "lied to'' about the desire of William and Harry to walk behind their mother's coffin.
In a BBC interview he said he raised objections with royal officials before being told his nephews wanted to do it, adding he later realised this was not the case.
He described the experience as the "most horrifying half hour of my life'' but said he believed it was a "million times worse'' for Diana's sons.
Harry revealed the true extent of his problems in an interview with the Telegraph describing how he sought counselling after two years of "total chaos'' having spent nearly 20 years "not thinking'' about the death of his mother.
Ahead of the 20th anniversary of The Princess' death, The Duke and Prince Harry wanted to celebrate her life and incredible legacy. pic.twitter.com/Fwe8OoSIKj— Kensington Palace (@KensingtonRoyal) August 30, 2017
The Prince said he stuck his "head in the sand" and refused to think about his mother because that would not bring her back.
"And then (I) started to have a few conversations and actually all of a sudden, all of this grief that I have never processed started to come to the forefront and I was like, there is actually a lot of stuff here that I need to deal with," he said.
He sought help after his older brother said he needed to deal with his feelings.
In the long run William, who is three years older than Harry, coped better with the loss although at the time he said he felt "very angry" and found it very difficult to talk about his mother's death.
His job may have helped him deal with his emotions as for much of his working life he has been called to the aftermath of traumatic incidents as an RAF search and rescue helicopter pilot or an air ambulance flyer.
Earlier this summer TRH's spoke about their mother and her inspiring work in the ITV documentary Diana, Our Mother: Her Life and Legacy. pic.twitter.com/ggI2wvjLa8— Kensington Palace (@KensingtonRoyal) August 30, 2017
Crews are likely to have been encouraged to debrief and talk about their experiences and feelings as a way of coping with the things they have seen.
The Duke told Tony Blair's former spin doctor Alastair Campbell, in a GQ magazine interview, the closest he got to mental health issues was the "trauma I suffered when I lost my mother".
He went on to say "I still haven't necessarily dealt with that grief as well as I could have done over the years", but had talked to family, friends and those around him he could trust.
Unlike brother Harry who has admitted to seeing, as the Telegraph interviewer put it, a "shrink", William said: "...on grief, I find talking about my mother and keeping her memory alive very important.
"I find it therapeutic to talk about her, and to talk about how I feel."
The life and death of Princess Diana
*July 1 1961: Diana is born at Park House in Sandringham, Norfolk.
* 1967: Her mother Frances leaves her husband for wallpaper heir Peter Shand Kydd. Six-year-old Diana stays with her father Viscount Althorp, later Earl Spencer.
* November 1977: Charles meets 16-year-old Lady Diana Spencer for the first time.
* 1978: Diana completes her education in Switzerland.
1979-81: She works as a kindergarten teacher in London.
* February 6 1981: Charles proposes to 19-year-old Diana.
* July 29 1981: Diana marries the Prince of Wales at St Paul's Cathedral and becomes HRH the Princess of Wales and a future Queen.
* June 21 1982: Prince William is born.
* September 15 1984: Prince Henry (known as Harry) is born.
* 1985: First reports of difficulties in the royal marriage emerge.
* 1986: Diana begins a five-year affair with cavalry officer James Hewitt. Charles turns to his former flame Camilla Parker Bowles.
The engagement today will be The Duke and Prince Harry's opportunity to publicly pay tribute to their mother, and all she achieved. pic.twitter.com/Ff6TGWU65P— Kensington Palace (@KensingtonRoyal) August 30, 2017
* 1989: The Princess helps break the stigma surrounding Aids and HIV when she shakes hands with a terminally ill patient and kisses him on the cheek at an east London hospice.
* June 1992: Andrew Morton's book Diana: Her True Story is published, alleging she is deeply unhappy, has attempted suicide and has suffered from bulimia.
* November 1992: Diana and Charles are dubbed "The Glums" for looking miserable on a tour to South Korea.
* December 9 1992: Prime Minister John Major announces Charles and Diana are to separate amicably.
* January 1993: The full transcript of the embarrassing "Camillagate" conversation is published in the UK.
* June 29 1994: Charles, in a television interview, says he was unfaithful to Diana after their marriage broke down.
* October 1994: Diana's former bodyguard and riding instructor James Hewitt publishes the book Princess in Love, in which he reveals his love for the princess.
The Duke and Duchess of Cambridge and Prince Harry arrive and make their way to The White Garden. pic.twitter.com/MtaJitNLtl— Kensington Palace (@KensingtonRoyal) August 30, 2017
* November 20 1995: Diana admits an affair with Hewitt in a BBC interview in which she famously says of her relationship with Charles had become crowded because "there were three of us in this marriage".
* August 28 1996: Charles and Diana divorce.
* January 15 1997: Diana visits mine victims in Bosnia and campaigns in Angola for an international ban on anti-personnel mines.
* August 31 1997: Diana and Dodi are killed in a car crash in Paris, along with their driver Henri Paul.
* September 6 1997: Diana's funeral takes place at Westminster Abbey.