When Prince Philip died earlier this year, many in the royal family remembered his sense of humor, his talent for carriage racing, and his love for the Queen. But a new documentary, "Philip: Prince, Husband, Father," which will air this week on ITV in the U.K., reveals that Philip was also a caring grandfather and a man who cared deeply for his grandchildren to grow up in a supportive He cared deeply for his grandchildren to grow up in a supportive environment.

The new documentary shows scenes from Princess Diana's funeral in 1997, with Prince Philip walking behind the coffin with Prince Charles, Prince William, and Prince Harry. The solemn occasion received extensive coverage, and the cameras were especially focused on the young princes.

According to the Daily Mail, Martin Palmer (one of the speakers for the new film and co-founder, with Prince Philip, of the Alliance for Religion and Conservation) asked Prince Philip about one moment at the funeral.

"There is a moment when they go under the arch of the Horse Guards Parade, where Prince Philip clearly said, 'Yes, I didn't think the cameras would see us.' ' You look at that moment and realize that here is a grandfather trying to help his young, very vulnerable grandson squirm through this terrible, terrible moment."

Prince Philip would have wanted this gesture to be distinct from his own upbringing, which Palmer describes as "dysfunctional." As he says in the film, "He knows what it's like to be part of a dysfunctional family, and he tried very hard not to let that happen to his grandchildren."

Also, according to the magazine, Prince Philip was not even initially set to participate in the procession behind the casket, but when William showed signs of reluctance, Prince Philip said he would participate as a show of support.

This anecdote reveals a gentler side of Prince Philip, different from the gruff and witty persona the public usually sees.

"Philip: Prince, Husband, Father" will air on ITV on Tuesday, but it is unclear if it will be available for streaming in the U.S.