Prince William, 40, is the eldest son of King Charles III and the first in line to the British throne. There are many rules and royal protocols which he is expected to follow, especially because he holds a senior title. That being said, there have been a handful of occasions where William has broken the rules, from growing a beard in 2008 to taking a selfie with a member of the public in 2022. The then-26-year-old made news around the world when he was photographed with a beard in 2008. He grew the beard during a 10-day trip to Barbados with the Navy's Special Boat Service, according to a report published in The Telegraph at the time. The prince may have grown the beard to disguise his identity during the trip, the publication reported, although this was never confirmed by the palace.According to an anonymous royal source who spoke to The Express in 2014, the late Queen Elizabeth didn't mind if royal men wore beards while serving in the armed forces, but she expected them to be clean-shaven when they returned home.Prince Harry appeared to confirm this rumor in his memoir, Spare, published on January 10, in which he writes that William was jealous that he was allowed to keep his beard for his royal wedding to Meghan Markle in 2018.Writing this, I remembered that William had a beard himself, and that granny and other people were the ones who told him to shave it off, Harry said during an interview with Tom Bradby for ITV on January 8.The difference for me, was, as I explained to my grandmother, that this beard, that I'm still wearing, felt to me at the time like the new Harry, as almost like a shield to my anxiety, he said.In his book, Harry wrote that William and King Charles weren't allowed to fly on the same plane together while he was growing up because two heirs shouldn't travel together in case there is an accident. William first broke this rule in 2014 when he flew with Kate Middleton and his eldest son and second in line, Prince George, to Australia for a royal tour of Australia and New Zealand. He regularly travels with George (age 9) and his other two children, Princess Charlotte (age 7) and Prince Louis (4), to public and private engagements. According to Hello Magazine, the rule hasn't been strictly followed by William because the monarch can override it until George turns 12, after which there will be no exceptions to the rule.As Britain has a constitutional monarchy, members of the royal family are supposed to remain politically neutral, and it's thought to be against protocol for royals to openly discuss politics in public. William appeared to break protocol in June 2019 when he openly discussed Brexit with farmers in the Lake District in England.According to ITV royal editor Chris Ship, William asked the farmers: Is Brexit a big concern?To which one farmer replied: I was very surprised that farmers voted for Brexit, to be honest. It was like turkeys voting for Christmas.Victoria Arbiter, a royal commentator, previously told Insider that it's considered against royal protocol to touch the royal family when you first meet them.What you would absolutely not do is launch and give a big hug to the Queen, or try to kiss them or put your arms around them. That's a big no-no, Arbiter said.Really it comes down to don't touch a royal. I'm sure there's lots of security reasons associated with it, but it's just not befitting of their position, she added.According to the royal family website, there are no obligatory codes of behavior when greeting the royals, but some members of the public like to observe the traditional forms, which includes a small neck bow for men or a curtsy for women.William doesn't seem to be strict when it comes to the traditional greetings, as he has been photographed hugging members of the public during various appearances, including during a visit to the Royal Marsden in Chelsea in 2019.Taking selfies with the royals is said to be strongly discouraged, as Insider previously reported. Meghan Markle declined a fan who asked to take a selfie with her during her first royal walkabout in Nottingham with Prince Harry in December 2017, telling them: We're not allowed to do selfies, according to royal author Victoria Murphy, who wrote about the exchange on Twitter at the time.However, this hasn't stopped William from taking photos with the public. In September 2022, he was pictured taking a selfie with a fan outside the royal family's Sandringham Estate during the mourning period for the late Queen Elizabeth.