Prince Harry and William Reveal Why Prince Philip Was 'the Heart of the Family' — Watch the Exclusive Video!
Getty Prince William, Queen Elizabeth, Prince Harry and Prince Philip
The intimate tribute film that features more than a dozen members of the royal family paying tribute to Prince Philip makes its debut in America next month.
From Prince William and Prince Harry to Philip and Queen Elizabeth's children — led by their oldest, Prince Charles — the royals share stories and insights from the Duke of Edinburgh's 99-year life in Prince Philip: The Royal Family Remembers this December 16 on discovery+.
In PEOPLE's exclusive new trailer for the documentary, William and Harry's cousin Princess Beatrice readies herself to speak about her beloved grandfather while William goofs around with the clapboard, laughing about what "I've signed myself up for."
William, 39, says his grandfather was "the heart of the family" and has "always been a huge presence behind everything we've done, really."
Meanwhile, 37-year-old Harry discusses Philip's forthright character: "What you see is what you got with my grandfather. The authenticness of him. He was unapologetically him."
Charles's wife, Camilla, Duchess of Cornwall marvels at Philip's astonishing life, saying, "I just asked him about his childhood. It was absolutely riveting."
RELATED: Remembering Prince Philip's Life in Photos
First airing in the U.K. in September, the documentary also sees Charles, 73, say of his father, 'We were lucky to have him for nearly 100 years."
Chris Jackson/Getty Images Queen and Duke of Edinburgh on Their 73rd Wedding Anniversary
Billed as a look at the "man behind the crown," it features Philip's former staffers and royal family talking about his life and legacy.
Originally conceived to mark Prince Philip's 100th birthday and showcasing clips from the Queen's private film collection, the documentary features interviews that were completed both before and after his death. It also goes inside Buckingham Palace into the Duke of Edinburgh's study, private office and library.
Steve Parsons/PA Images via Getty Queen Elizabeth and Prince Philip
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Philip died on April 9, just two months before what would have been his 100th birthday, and the family gathered for his funeral on April 17 at St. George's Chapel in Windsor Castle.
It would have been Philip and the Queen's 74th wedding anniversary on Saturday. Two of his granddaughters Princess Eugenie and Zara Tindall, along with their families, paid a subtle but poignant tribute on Sunday. Their sons August Brooksbank and Lucas Tindall — both of whom have Philip as a middle name — were baptized in the presence of the Queen, 95, and other members of the royal family at the Royal Chapel of All Saints in Windsor Great Park.
Prince Philip: The Royal Family Remembers launches exclusively on discovery+ on December 16.