Celebrity Prince Harry Princes Harry and William Reportedly Both Have "Extreme Mood Swings" A royal expert says Princess Diana did, too. By Christopher Luu Christopher Luu Instagram Twitter Christopher is a Southern California-based editor and has been with InStyle since 2018. He covers all things entertainment, celebrity, and culture. InStyle's editorial guidelines Published on April 25, 2022 @ 03:53PM Pin Share Tweet Email Photo: Photo by Mark Cuthbert/UK Press via Getty Images When we see Prince Harry and Prince William out performing their princely duties, like unveiling statues and visiting charities, they're cool, collected, and completely calm. However, just like anyone, the royals can lose their tempers sometimes and a royal expert explained to the Daily Mail that both Will and Harry are notorious for having hot heads. Robert Jobson, a former courtier, also noted that it's something that the brothers got from their mother, Princess Diana. "In private, the Duke of Cambridge has a notably short fuse. His fiery temper can blow up at any time — usually when he's frustrated or when it comes to issues regarding his family," Jobson wrote. "Even senior members of his circle will 'check which way the wind is blowing' before becoming too self-assured in his presence or raising problematic issues that might be better addressed at another time." Prince Harry and Prince William Reportedly Had Major Tension Way Before Meghan Markle "They both have quite extreme mood swings, just as Diana did," he added. "She could be your best friend one minute and the next your worst enemy." And while the public will probably never see the two lose their composure, Jobson noted that Kate Middleton has — and she often had to act as a mediator between the two using her "deft diplomatic touch." While there have been rumors of Harry wanting a mediator to get involved to help smooth over any familial drama, sources close to the Firm say that it could be Kate. "If anyone can bring peace to the royals, Kate can. Kate is a brilliant arbiter and peacemaker," a source told Express. "Every bone in her body is about making friends and doing the best she can ... she is trying to mediate."