The royals took part in recorded interviews for the Prince Philip: The Royal Family Remembers documentary, which airs at 9pm on BBC One this Wednesday.
Harry called them “the most adorable couple”, while Zara said old footage of the pair makes her “hair stand on end” and Eugenie named them “the most remarkable” pair the world has seen.
“The two of them together were just the most adorable couple,” recalled Harry.
“I don’t know if anyone’s ever described them as adorable but, to me, knowing the cheekiness of him and knowing that behind what the world sees you have two individuals who were very much in love, and both at a very young age dedicated both of their lives to service.
“The places these two travelled, the things they saw, the experiences they went through: that is an incredible bond between two people.”
Looking at their wedding photo, Eugenie added: “It’s amazing to see their partnership. And just what a good looking couple! Wow.
“It’s unbelievable looking at this now, realising how much they created from this. They’re one of the most remarkable couples I think the world has even seen and will ever see.
“And granny has been able to be the person she is with the love and support from grandpa.”
“It just makes your hair stand on end, doesn’t it?” said Zara. “When all the old footage comes up it’s so nice to see how they were with each other before family and before anyone else came along.”
Prince Charles , Prince William and Prince Andrew also speak candidly in the documentary, which honours Prince Philip’s life and legacy following his death in April this year.
Prince Philip: The Royal Family Remembers, Wednesday at 9pm on BBC One
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