Remembering Diana on the anniversary of her death, a friend posted a photo of a happy memory.
Princess Diana in Pink Gingham Pants
Credit: Tim Graham / Contributor/Getty Images

Today marks the 21stanniversary of the death of Princess Diana. Twenty-one years ago today, The People's Princess died in a horrible car accident in that Paris tunnel and she remains in our memories, forever 36 years young. All around the world, people gathered and prayed for the princess they all felt so connected to even though most had never met her. We collectively wept as we watched young Prince William and Prince Harry walk behind their mother's casket and as we listened to Elton John sing Candle in the Wind, re-written to honor Diana.

Over two decades later, the world still mourns the loss of "England's rose." Today, just as they did twenty-one years ago, flowers, balloons, and memorials have been placed at the gates of Kensington Palace, Diana's former home and now the home to her children. William and Harry are taking today to remember their mother privately with the wives and grandchildren she never had the opportunity to meet.

Balloons and Flowers at Kensington Palace Gates for Diana
Credit: Barcroft Media / Contributor/Getty Images

But one of Diana's close friends has taken to social media to remind us, however sad her end, that in life, her friend was full of joy.

Rosa Monckton took to Twitter and posted a photo of Diana wearing a sweatshirt and casual pants, leaned back in an airplane seat, eyes closed tight and her mouth in a broad, open smile. She is clearly having one of those deep belly laughs, and her expression exudes happiness.

Monckton captioned her photo, "Diana as I remember her. Not enough is written about her sense of fun and zest for life. Friend and wonderful godmother to Domenica. RIP."

Monckton was a close friend and confidant to Diana and even named her godmother to her daughter, Domencia. Monckton's daughter was born with Down syndrome in 1995, and Monckton spoke to PEOPLE in 2016 about what a huge support the Princess of Wales was during that time. She went to appointments with the expectant mother and offered her heartfelt advice. "She said, ‘Believe in her, love her and I'll be there every step of the way.' She already had that vision of what Domenica could become, which I simply couldn't see," Monckton recalled.

Domencia is now 23 years old and thriving. She inspired her mother to launch the charity, Team Domencia, to help others who suffer from learning disabilities to find a place in the workplace and to feel full accepted by society.

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And that spirit of helping those in need is, perhaps, Diana's strongest legacy and it's one that both of her sons have carried on proudly. William and Harry have continued supporting many of her causes and also honor their mother by championing many of their own. To learn more about how you can help their efforts, check out the Royal Foundation here.