The Duke of Edinburgh was the longest-serving royal consort in history, but he was also a caring grandfather.
A new ITV documentary shows the moment Prince Philip comforted his young grandson, Prince William, at Diana, Princess of Wales's funeral in September 1997.
READ: Prince Charles pays tribute to Prince Philip during visit to 'special place'
WATCH: Touching moment Prince Philip comforts Prince William at Diana's funeral
Speaking in the documentary, Martin Palmer, former religious adviser to the Duke, says: "There's a moment where they go under the Horse Guards Parade arch, where it's quite clear that Prince Philip - and I asked about this and he said, 'Yes I didn't think the cameras could see us'.
"At that point he turns to William, who he's walking beside, and comforts him. You've just got to watch that moment and realise, here is a grandfather who is trying to help his young, very vulnerable grandson struggle through this awful, awful moment."
The incredibly moving footage from the funeral service shows the Duke of Edinburgh placing a protective hand on his grandson's back.
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The Duke walked beside Prince William
Princes William and Harry were just 15 and 12 respectively when their mother Diana was tragically killed in a car crash in Paris in August 1997. The royal brothers were accompanied by Prince Philip, their father, the Prince of Wales, and their uncle, Charles Spencer, as they walked behind the funeral cortège from Kensington Palace to Westminster Abbey for the service.
William and Harry both walked in the procession at the Duke's funeral in April. Prince Philip sadly passed away at the age of 99 at Windsor Castle on 9 April.
The new ITV documentary puts Prince Philip's own words front and centre, drawing on rare archive and audio recordings spanning 80 years, to let us hear the Duke talk frankly about the role of the monarchy, press intrusion, and Prince Charles' future.
Philip: Prince, Husband, Father, 9pm, ITV, Tuesday 21 December.
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