Prince William and Prince Harry only got to spend a few years with their mom, Princess Diana, because the royal passed away on Aug. 31, 1997.

While she was still alive, the Princess of Wales admitted to struggling with her mental health. On the online forum site Quora, royal fans talked about whether or not the royal siblings were aware of what their mom was going through years ago.

Chrissie Nyssen said that Prince William and Prince Harry both knew that Princess Diana was struggling with her mental health. The royal fan cited the time that Prince William became upset with his mom after she was interviewed by Martin Bashir for Panorama.

“Even at that tender age, he could tell that there was something wrong and he instinctively felt that her behavior, in that case, was not appropriate,” she said.

Lisa Niehoff said that she’s wondering whether or not Prince William and Prince Harry became involved with promoting the importance of mental health partially because of Princess Diana’s struggles. She said that the Princess of Wales might have had mood swings when she was still alive that her sons witnessed.

Alexandra Roach, a resident of the United Kingdom, said that Prince William and Prince Harry couldn’t have been aware of their mom’s struggles back in the day because they were still very young.

“And you are living with something you don’t necessarily realize isn’t normal and for all her faults she did love them and may have tried to protect them and they were away at school. And their lives are not normal generally,” she said.

Marie Helene Avenant, a teacher in grammar school said that Prince William might have been aware of it and he may have also known that his mom was suffering from eating disorders. As for Prince Harry, he would have been very unhappy because of what Princess Diana was going through at that time.

Princes William, Harry, Princess Diana
Princess Diana went on a three-day vacation at Disney World with her sons in 1993. Pictured: Princess Diana, Princes William, Harry applaud during the Wales vs France Five Nations Cup match at Cardiff Arms Park on February 1, 1992.` Getty Images/Jean-Pierre Muller/AFP