Royals British Royal Family British Royal Family Style Kate Middleton Responds When a Fan Tells Her She Will Be a 'Brilliant Princess of Wales' The Duchess of Cambridge will likely inherit Princess Diana's title when Prince William becomes the immediate heir to the throne By Erin Hill Erin Hill Erin Hill is the Senior Editor, Royals at PEOPLE. She has reported on Royals for the brand since 2015. Erin previously worked at PARADE Magazine and The Knot. People Editorial Guidelines Published on June 14, 2022 09:40AM EDT Kate Middleton. Photo: Chris Jackson/Getty Kate Middleton had a heartfelt reaction when a fan paid her a meaningful compliment during an outing in Wales earlier this month. On June 4, Kate, 40, and Prince William, 39, visited Cardiff Castle alongside their children, Prince George, 8, and Princess Charlotte, 7, in honor of Queen Elizabeth's Platinum Jubilee celebrations. During the outing, the family chatted with well-wishers outside the castle. In one sweet moment, a woman shook Kate's hand and told her: "You're going to be a brilliant Princess of Wales." Appearing very touched, Kate replied: "Oh, that's very kind." Gesturing towards William, she added, "I'm in good hands." Kate Middleton Attends Order of the Garter 14 Years After Making Debut as Prince William's Girlfriend The moment was captured on camera by Twitter user @Hellen3030, who tells PEOPLE: "The Cambridges are humble and a lovely family. I flew last minute from Miami to attend the Platinum Jubilee and decided to go to Cardiff the day before. I met wonderful people from all over the world wanting to meet them. We had no idea they were bringing Prince George and Princess Charlotte until later on. Once we met the Cambridges, we were all mesmerized by them. I missed my train back to London and arrived late to the Platinum Party at the Palace, but it was all worth it!" Kate, who received the title of the Duchess of Cambridge upon her wedding to William in 2011, will likely be known as the Princess of Wales (like her late mother-in-law, Princess Diana, before her) when William takes the title of Prince of Wales after his father Prince Charles becomes King. The mother of three faces mounting public expectations as future Queen. "Those who know her say there is a real core of strength, and she did set her mind to the job," Sarah Gristwood, author of Elizabeth: The Queen and the Crown, previously told PEOPLE. "But at the same time, she'd have to be superhuman not to feel the pressure." The Cambridges. Ben Birchall/PA Images via Getty As the future Queen raising a future King, Kate is expected to flawlessly fulfill multiple roles: princess, supportive spouse, hands-on mom, international bridge-builder, charity advocate, style icon and more. "The future Queen is a role model to the U.K. but also to the world, which means all eyes are on you," says royal etiquette expert Myka Meier, author of Modern Etiquette Made Easy. "The added pressure of having cameras everywhere to catch even the slightest eye movement makes everything she does a conscious effort. From the perfectly poised posture to the way she descends a staircase or gets out of a car—it is all carefully done." Prince William, Kate Middleton, Princess Charlotte and Prince George in Wales on June 4. PA Images / Alamy Stock Photo Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! Like Queen Elizabeth, Kate doesn't let the pressure show. And she has found increasing confidence with her royal work, which has helped propel her forward. "Catherine is the sort of woman who will take on whatever she needs to," a close source tells PEOPLE. "If she needs to step up to the plate, she does it—and she always has."