As the 20th anniversary of Princess Diana's death rapidly approaches, Prince Harry and Prince William are finally ready to talk about their mother's tragic passing. Not only have they recently opened up to reporters about the trying time, but they will also both be featured in an upcoming BBC documentary about the days surrounding Diana's death, aptly titled Diana.

"Part of the reason why Harry and I want to do this is because we feel we owe it to her," William, 34, says in the film, according to the BBC. "I think an element of it is feeling like we let her down when we were younger. We couldn't protect her." He adds, "We feel we at least owe her, 20 years on, to stand up for her name and remind everybody of the character and person that she was—do our duties as sons in protecting her."

Harry, 32, echoes his brother's sentiments, saying, "I think it's never going to be easy for the two of us to talk about our mother, but 20 years on seems like a good time to remind people of the difference that she made not just to the royal family but also to the world."

In the documentary, William and Harry will talk about the aftermath of the death of their mother, who was 36 when she was fatally injured in a car crash in Paris on Aug. 31, 1997. At the time of her death, William was 15, and Harry was 12.

According to the BBC, Harry reflects in the documentary about the "shocking" amount of emotion shown for Diana in the days following her death. "It was beautiful at the same time, and it was amazing, now looking back at it, it was amazing that our mother had such a huge effect on so many people," he says. "When you're that young and something like that happens to you, I think it's lodged in here, there, wherever—in your heart, in your head—and it stays there for a very, very long time."

Diana will also feature interviews with friends, political figures, and journalists. The 90-minute film will premiere ahead of the 20th anniversary of the accident this August.

Earlier this year, Harry opened up about the lasting impact of the tragedy on his own mental health, telling The Telegraph that immediately following his mother's death, he felt numb. He said, "I can safely say that losing my mum at the age of 12, and therefore shutting down all of my emotions for the last 20 years, has had a quite serious effect on not only my personal life but my work as well." Harry added, "I have probably been very close to a complete breakdown on numerous occasions when all sorts of grief and sort of lies and misconceptions and everything are coming to you from every angle."

Harry admitted that it was only recently that, at the urging of his older brother, he sought help from a therapist and learned to let his feelings out. "Because of the process I have been through over the past two-and-a-half years, I've now been able to take my work seriously, been able to take my private life seriously as well, and been able to put blood, sweat and tears into the things that really make a difference and things that I think will make a difference to everybody else," he said.

Related: Prince Harry and Meghan Markle Are Reportedly Moving Into Kensington Palace Together

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