Prince Harry is wrapping up his U.K. trip with a visit to the only charity established in his late mother Princess Diana’s name during his latest U.K. visit.

On Sept. 11, the Duke of Sussex, 40, attended an outing for The Diana Award in London, joining a group of young people showcasing how their own social action initiatives have boosted their mental health.

The event follows his trip to Nottingham on Tuesday, Sept. 8, and outings in London, including his first in-person meeting with his father, King Charles, in 19 months.

This U.K. trip is one of the longest Harry has spent in his home country since the death and funeral of his grandmother, Queen Elizabeth, in 2022. He and his wife, Meghan Markle, stepped back from their royal roles in 2020 and relocated to the Duchess of Sussex’s home state of California.

At the event, Harry paid tribute to his mom, saying, “My mother believed in the power and agency of young people to positively impact the world. The Diana Award continues her legacy by putting young people at the heart of everything they do. Today is a perfect example of that. My message to everyone is don’t stand still, don’t stay silent – make them hear you because you speak for the majority.”

He was talking after a discussion led by Dan Lawes, a political activist and children’s rights campaigner from Manchester, who also serves as a trustee for The Diana Award. The panel featured Lottie Leach, Elsa Arnold, and Idorenyin Hope Akpan, all 23, who have actively participated in youth-led social action through the charity.

Following the discussion, Harry shared his reflections on the stories and insights he had just heard. “Getting involved in peaceful social action takes courage and determination. Young people see the issues society faces close up — whether that’s poor mental health or the consequences of inequalities. But you don’t stand still; your empathy and compassion drive you to make change. Purpose combined with action can help overcome a sense of hopelessness, and that’s exactly what you’ve shown today.”

“When you spoke about how taking action gave you purpose, confidence, and joy, it was more powerful than any statistic. It reminded me that agency is not a luxury for young people, it is a lifeline.”

The Diana Award is one of the few causes that unites both Harry and Prince William, 43, despite their ongoing rift. The brothers regularly — though separately — participate in events honoring young people making a difference in communities around the world.

Despite their shared commitment, Harry attended the event without his brother and is not expected to see William during his U.K. visit, as tensions between the siblings remain unresolved.

Tessy Ojo, the charity’s CEO, told PEOPLE in August, “They see that next generation who are instilling her legacy and values into generations to come. I’m sure they do it with their own individual families, but what the Diana Award does is continue that legacy and pass that legacy and values on to generations of young people who would never have met her.”

Ojo added that the princes embody the values of their mother: duty, service, empathy and selflessness, “that ability to ally with, and think about others, and empathy to see — so that other people’s plights become visible.”

On Thursday, the young people addressed an audience of leaders and changemakers at a London event hosted by ServiceNow, marking one year since the launch of The Diana Award’s “Decade of Youth Well-Being,” a program supported by Prince Harry.

The event followed last September’s launch of the Decade of Youth Well-Being, which Harry joined in New York City, participating in a panel discussion and speaking about the initiative. The program is described as a “bold, ambitious, and collaborative plan to harness the power of young people.”

Ojo said: “One in five young people is living with a diagnosable mental health condition, and four in ten feel powerless about their future. The crisis is real. This is why The Diana Award launched the Decade of Youth Wellbeing a year ago, prioritizing mental health for young people globally. When young people are trusted to lead and take action, their well-being rises, their resilience grows, and hope is restored. Put simply, action heals minds.”

The Duke of Sussex’s latest appearance follows his Sept. 10 meeting at Clarence House with King Charles, 76. It was their first meeting face-to-face since February 2024, after the palace announced that the monarch was receiving treatment for cancer.

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Following a stop at Imperial College London’s Centre for Blast Injury Studies, Harry arrived by car at Clarence House, King Charles’ London home, around 5:20 p.m., local time.

The Duke of Sussex was inside for about 55 minutes before departing.

After the meeting, Buckingham Palace confirmed that the King had a private tea at Clarence House with Prince Harry and said no additional details would be shared. A spokesperson for the Duke of Sussex echoed the same, reiterating that father and son met for tea and that there would be no further comment.

Soon after, a reporter asked Harry how his father was, and he replied, “Yes, he’s great, thank you.”