The Prince of Wales has revealed the last conversation he had with his father, the Duke of Edinburgh, before the almost-centenarian died on 9 April.
In the documentary, titled Prince Philip: The Royal Family Remembers, Charles says he told Philip: “We’re talking about your birthday.”
He then repeated himself louder for the duke, who was hard of hearing: “We’re talking about your birthday! And whether there’s going to be reception!”
Philip replied: “Well, I’ve got to be alive for it, haven’t I?”
Charles said: “I knew you’d say that!”
The Duke of Edinburgh died at Windsor Castle aged 99, shortly before what would have been his 100th birthday on 10 June.
In the same interview, Charles said the royal family were “lucky” to have had Philip for nearly 100 years.
The documentary was originally commissioned to mark his centenary, but has been transformed into a tribute.
It features interviews with members of the royal family, including Charles, Prince William and Prince Harry, before and after Philip’s death.
The Duke of Cambridge shared an anecdote about his grandfather, recalling a drive they took to a remote spot on the Queen’s Balmoral estate.
During the drive, they came across a group of young walkers undertaking the Duke of Edinburgh’s Award. According to William, Philip wound down his window to greet the walkers and ask them: “How are you getting on?”
“To which the smallest young chap at the back turned around and effectively said, ‘Jog on Grandpa!’,” said William, adding that his grandfather found the exchange hilarious and remarked: “The youth of today!”
The programme is the first “family project” Harry has taken part in since he stepped down as a senior royal before moving to California with Meghan Markle.
Harry said: “From my grandmother’s perspective, to have someone like that on your shoulder for 73 years of marriage – it doesn’t get better than that.”
Zara Tindall, the daughter of Princess Anne and Philip’s eldest granddaughter, said her grandfather “absolutely hated” getting older.
“He was the worst patient in the world! But, actually, you never really prepare yourself for losing him because he was always there,” she said.
Prince Philip: The Royal Family Remembers airs on BBC One at 9pm on Wednesday 22 September.
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