Prince William and Prince George recently traveled to Barcelona together to watch a soccer match . But according to one report, the two royals broke protocol during their commercial flight to Spain .

Fellow passengers were reportedly surprised when they spotted two future Kings traveling on a commercial flight together, seemingly breaking a significant Royal Family rule . The father and son traveled to Spain to watch their favorite soccer team, Aston Villa , play against Barcelona in the Champions League on November 3.

As reported by Royal Central , footage of William and George disembarking from "what appeared to be a British Airways flight to Barcelona" has been posted online .

Per the outlet, "Their decision to travel together is particularly notable given the traditional arrangements surrounding the Royal Family's line of succession , which have historically discouraged two direct heirs from sharing an aircraft."

Prince William and Prince George watching a soccer match in Barcelona on November…