How do Prince William and Harry pay tribute to Princess Diana in Diana, Our Mother – Her Life and Legacy on ITV

WHILE Diana was known to the world as "The People's Princess" - to the young princes William and Harry she was much more.

The documentary was commissioned to coincide with the 20th anniversary of Princess Diana's death. In it, Prince William and Prince Harry speak at great length over their memories and emotions of their late mother. Here's what the future king and his brother have had to say...

How are Prince William and Prince Harry involved in the documentary?

Princess Diana's two children, Prince William and Prince Harry, were just 15 and 12 when their beloved mother died.

The two royals will talk openly and in depth about their mum and how she has influenced and shaped their lives.

Both offer their own perspectives on Diana's contribution to public life through her endless charity and humanitarian work both in the UK and abroad.

Their participation in the documentary follows recent candid conversations both Princes have had about their mother while promoting their mental health charity, Heads Together.

Prince William, 34, said during a documentary titled Mind Over Marathon: "I still feel 20 years later with my mother . . .   I still feel the shock within me.

“You think shock can’t last that long but it does. You never get over it. It’s such an unbelievably big moment in your life."

Meanwhile Prince Harry, 32, told The Daily Telegraph he turned to therapy after coming “close to a complete breakdown” over the loss of his mother.

He added he had turned to boxing as a means of safely taking out his aggression and frustration as he bottled up his emotions.

What else can viewers expect from the documentary?

As well as her sons, a number of other key figures in Princess Diana's life will speak about her in the documentary.

Jo Clinton-Davis, who is the Controller of Factual at ITV and commissioned the series, said of the programme: "This new ITV film will offer viewers a fresh and revealing insight into Princess Diana through the personal and intimate reflections of her two sons and of her friends and family, many of whom have never spoken before, to bring together a definitive portrait of a unique person who touched the lives of millions."

When is the documentary about Diana, Princess of Wales on TV?

ITV joined forces with American network HBO to produce the new documentary about Princess Diana.

The programme celebrates her life and work as the nation prepares for the 20th anniversary of her shocking death on August 31.

The programme repeats tonight (Sunday, July 30) at 6:30pm on ITV.