Prince William and his father, King Charles, are the two most important members of the royal family. William is first in line for the throne behind his dad, but William and his wife, Kate Middleton, are arguably the bigger faces of the royal family. William already reportedly has big plans for the monarchy when he takes the throne, but in a recent royal appearance, William said something that some interpreted as a subtle insult toward his father. And those close to the family have reportedly warned William to “be careful.”

Prince William’s recent comment has some giving the prince a stern warning

William and Charles generally have a good relationship, and they are both working together to build the monarchy into something new and more modern. Someday, William will take over for his father, and rumor has it Charles isn’t doing too much to change things because he knows he won’t build a legacy on the throne.

However, William’s recent words at a royal event had some thinking he made a subtle insult toward Charles and monarchs before him. While in Singapore, William said that the royal family, who does tons of charitable work, has a habit of finding “loads of causes that you sort of turn up and keep an eye on” as opposed to making a true difference. Some saw this as a dig at Charles and the way he has led as the monarch, and it prompted a warning from some royal friends.

“William is entitled to make these comments, which, frankly, are pretty unremarkable, but part of the reason the marriage with Camilla has worked so well is that she understands that Charles is the star,” a royal friend reportedly said, per The Daily Beast. “William has to be careful not to wake the green-eyed monster.”

King Charles has reportedly ‘scolded’ Prince William for taking attention away from him

Charles and William’s relationship has been clouded by William’s popularity for many years, according to Prince Harry. In his “Spare” memoir, Harry noted that William was once “scolded” by his father over attention.

“Pa and Camilla didn’t like Willy and Kate drawing attention away from them or their causes. They’d openly scolded Willy about it many times,” Harry wrote in his book. If this is true, then it makes sense that William’s dig at the royal family could be seen by Charles as something worth getting upset over.

William continues to prepare himself for the throne by shaping himself into a voice for the people. He and Kate have taken on fewer patronages than past royals with the hope of creating a greater focus on causes that mean the most to them, which ties into William’s words about not liking the idea of “loads of causes.” William recently attended the Earthshot Prize ceremony in Singapore, where he vowed to take his climate change initiative even further than any former royals have. For now, though, Charles is still king, and while all eyes are on William, Charles seems to want to maintain the distance between him being the monarch and his son still being a prince.