Prince Harry remembered his mother Princess Diana while speaking at a polo match in support of his Sentebale charity on Thursday.

The Duke of Sussex reflected on the upcoming 25th anniversary of Diana’s death in his Sentebale ISPS Handa Polo Cup speech, sharing how he wishes his kids Archie, 3, and Lilibet, 1, whom he shares with Meghan Markle, could have met her.

Harry is focusing on keeping Diana’s memory and the incredible work that she did alive, founding Sentebale with Prince Seeiso back in 2006. The organization “gives hope to children and young people affected by HIV in Lesotho and Botswana.”

Harry shared at the event in Aspen, Colorado: “In Sesotho, the language of the Basotho, the word Sentebale means ‘forget-me-not.’

“Next week is the 25th anniversary of my mother’s death, and she most certainly will never be forgotten. I want it to be a day filled with memories of her incredible work and love for the way that she did it. I want it to be a day to share the spirit of my mum with my family, with my children, who I wish could have met her.”

READ MORE: Prince Harry And Meghan Markle Have Adopted A Rescue Beagle Named Mamma Mia

Harry said that he hopes to “do her proud” every day, adding: “She was tireless in her work to support and destigmatize those experiencing HIV and AIDS. Fittingly, her favourite flowers were ‘forget-me-nots.'”

The duke went on, “I hope we can remember my mother’s legacy by recommitting to those that we serve, whoever and wherever they may be.

“For Sentebale, our commitment is to ending HIV and providing meaningful care and support for the children and young people whose lives have been affected by this disease. Because they too will never be forgotten.”

READ MORE: Meghan Markle Only Experienced ‘The Negative Connotation Behind The Word Ambitious’ After Dating Prince Harry

Diana died on August 31, 1997, at age 36 in a car crash in Paris. Harry was just 12 years old at the time; his brother Prince William was 15.