The sons of the late Princess Diana will appear in the NBC documentary, “Diana, 7 Days,” and talk about the events and repercussions of the death of their mother. It will be 20 years to the day the Princess of Wales died in a car crash in Paris.

The documentary is two hours long and will air September 1, the day following the 20th anniversary of Diana’s death.

According to Entertainment Weekly, the documentary will focus on the historic days leading to the fateful car accident that claimed the life of the princess and how the tragic event altered the lives of William and Harry.

William and Harry’s initial reactions

Prince William and Prince Harry shared their initial reactions to the news of Diana’s death, the huge public mourning, and the funeral day. They shared personal memories and what Diana meant to them both in the past and the present.

Prince Harry said the outpouring of emotion and love for Diana “was quite shocking.” The prince said that it was amazing their mother had such a huge effect on so many people. “It was beautiful at the same time, and it was amazing now looking back at it.”

'We feel we owe it to her.'

The princes were interviewed on-camera where they both shared and reflected on the tragic event and recollections of Princess Diana.

According to EW, Prince William said the feeling that they owe it to their mother was part of the reason why he and Prince Harry did the interview.

The Duke of Cambridge talked further about the feeling they let their mother down when they were younger and they “couldn’t protect her.”

Two decades later, Prince William and Prince Harry feel the need to stand up for her name and remind people of Diana’s character and person. “Do our duties as sons in protecting her," said Prince William.

Tony Blair will also appear

Aside from the two princes, “Diana, 7 Days,” will also feature a number of notable personalities like former Labor Prime Minister Tony Blair, who called Diana, the People’s Princess. Her brother, Earl Spencer, other family members, close friends, journalist, and personalities in politics will appear as well.

The NBC documentary follows another biopic about the princess titled, “Diana, Our Mother: Her Life and Legacy,” which aired on HBO the previous month. Prince William and Prince Harry were also actively part of the documentary, which focused on Diana’s presence as a mother.

It would appear that Prince William and Prince Harry are opening up to the public as to the subject of Princess Diana to remind people of who she was and the legacies she left.