Prince George will not be expected to serve in the armed forces before becoming King.
The nine-year-old royal, who is second in line to the throne, will reportedly not be required to serve in the military before acceding to the throne in what is set to mark a significant break from royal tradition.
The monarch is Commander-in-Chief of Britain's armed forces and George's father Prince William, uncle Prince Harry, grandfather King Charles and late great-grandmother Queen Elizabeth all followed tradition by serving in the military but a friend of William's says that "the rules are different now".
They told the Mail on Sunday newspaper: "In theory, there is nothing to stop George from pursuing a career as an astronaut, for example, if that's what he wants, and then becoming King later.
"The rules are different now, he wouldn't necessarily have to follow the old formula of going into the military and then royal life."
Royal expert and biographer Hugo Vickers described the move as "significant" and says it shows "that times are moving on".
He said: "This is significant because it shows that times are moving on. I'm all for people keeping up with the times providing they don't throw tradition out of the window.
"For King Charles, his naval service in the 1970s was very helpful. It showed the country that he was gainfully employed and it was a role where he would not be using his title for commercial gain.
"Military service allows members of the royal family to have a sense of normal life, grants them a certain amount of freedom and teaches them all sorts of timekeeping and presentation skills which prove to be important for royal duties."
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