Princess Diana and a 10-Year-Old Prince Harry Shared This Sweet Moment 25 Years Ago This Week

Princess Diana's maternal instincts were always on display.

Twenty-five years ago, the late royal attended a ceremony at London's Hyde Park marking the 50th anniversary of the end of World War II in Europe, known as Victory in Europe Day or VE Day. She sat between her young two sons, Prince William and Prince Harry in the front row for the event.

Diana lovingly held Harry's hand as the 10-year-old royal sat on the edge of his chair to be closer to his mother. At one point, she offered her son a drink of water.

Prince Harry also got out of his seat to give someone a wave as his big brother, 12 at the time, smiled.

Prince William and Prince Harry have often spoken about the special times they spent with their mother in Kensington Palace — and a heartfelt letter being auctioned in the U.K. shows a tiny glimpse of just how meaningful that time was.

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Steve Nicholson/Mirrorpix/Getty Prince Charles, Prince William, Princess Diana and Prince Harry

Prince Charles, Prince William, Princess Diana and Prince Harry

The handwritten note, dated June 21, 1989, was sent by Diana to Sergeant George Plumb of Scotland Yard’s elite Close Protection Group to thank him for organizing a special motorcycle display for William’s 7th birthday.

Written on official Kensington Palace paper, it includes Diana's signature and the youthful scrawled signatures of William and a then 5-year-old Harry.

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“Dear Sgt Plumb, It was so very kind of you and your team to have come here today on William’s birthday,” Diana writes in the letter. “I cannot begin to tell you what pleasure the display gave to all those little people and their mothers!

“I know how particularly busy you all are at the moment, so it meant even more to us that you and the motorbike boys were able to take part in the birthday celebrations! This comes with our warmest possible thanks.

“Yours sincerely Diana, William, Harry.”

A.G. Carrick/Diana Memorial Fund/Getty Princess Diana, Prince William and Prince Harry

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This year, Queen Elizabeth is set to give an address for the 75th anniversary of VE Day at 9 p.m. — the same time her father, King George VI, gave a radio message at the end of the war in 1945.

Prince Charles and his wife Camilla, Duchess of Cornwall led the nation in two minutes of silence, and the heir also read an excerpt from his grandfather's diary about the end of the war.