Prince Philip was reportedly the one who encouraged Prince William to walk behind Princess Diana’s coffin after the latter’s tragic death in 1997. Details about the royal relatives’ conversation were unveiled in a YouTube documentary.

In June 2012, royal correspondent Jennie Bond said in “Prince William At Thirty” that the Duke of Cambridge didn’t know until the last minute if he would walk behind his mom’s coffin. Prince Philip quickly stepped in and asked Prince William if he would walk with him.

Queen Elizabeth II’s cousin, Lady Elizabeth Anson, said that Prince William thought it was such a wonderful thing for his grandfather to also walk with him. The dad of three never forgot about what Prince Philip did for him at that time.

Former ITN royal correspondent Nicholas Owen said that it was such a beautiful sight to see three generations of royals walking behind the coffin. Prince Charles, Prince Harry and Princess Diana’s brother, Charles Spencer, were also there.

“And then the coffin comes along and there are the boys, walking along behind them with the Duke of Edinburgh and Prince Charles — no one expected that!” Owen said.

Princess Diana’s body was carried from Kensington Palace on a gun carriage along Hyde Park to St. James’s Palace, where her remains were kept for five days. She was later on moved back to Kensington Palace.

The Union Flag on top of the palace was lowered to a half-mast, and a ceremony was held at Westminster Abbey. Huge crowds gathered outside the palace grounds to pay their respects to the Princess of Wales. But everyone stood in silence during the entire ceremony.

Princess Diana passed away following a fatal car crash in Paris. At that time, she was with her boyfriend Dodi Al Fayed, who also passed away following the crash. Prince William and Prince Harry were just 14 and 11 years old at that time.

Princess Diana's Coffin The coffin of Diana, Princess of Wales, is carried into Westminster Abbey by the bearer party of Welsh Guardsmen for her funeral ADAM BUTLER/AFP/Getty Images