Prince George and Princess Charlotte will be separated when royal rule comes into force

Prince George is set for a big change when he turns 12 in July next year due to a traditional Royal rule. The protocol will come into effect because of his standing as second in line to the throne after his dad, Prince William, as it restricts certain royals from travelling together to the same place.

The insight into this intriguing regulation came from King Charles's ex-pilot, Graham Laurie, who revealed: "We flew all four: the Prince, the Princess, Prince William and Prince Harry, up until Prince William was 12 years old".

He said once William hit 12, they required a special document from the ruling monarch, the late Queen Elizabeth, giving them special permission to travel together.

"After that, he had to have a separate aircraft and we could only fly all four together when they were young with the written permission of Her Majesty.

"When William became 12, he would fly normally in a 125 from Northolt and we would fly the 146 out with the other three on.", reports the Express.

While the provision will soon apply to young Prince George, it's yet to be seen whether it will require him to fly separately from William, Kate Middleton and his siblings, Charlotte and Louis, or if Prince William will fly solo while George travels with his mum and siblings.

Another possibility is that Prince William might travel with either Charlotte or Louis (or both), while George accompanies his mum, the Princess of Wales

This Royal ban can be overlooked with written permission from King Charles as the monarch, but the heirs travelling together represents a risk for the future of the monarchy in case of a crash. In the past, three royals have died in plane crashes.

Princess Cecilie, who died in a crash in 1937, followed by the late Queen's uncle Prince George, Duke of Kent in 1942, and her cousin, Prince William of Gloucester, whose death at the Goodyear International Air Trophy in 1972 was witnessed by around 30,000 spectators.

Princess Cecilia - the third eldest sister of Prince Philip, Duke of Edinburgh, was just 26 when the plane she was travelling on to the UK to attend a family wedding crashed near Ostend in Belgium.

While Prince George, who was a serving RAF officer, was killed in the Dunbeath air crash in the Scottish Highlands, in which 14 of the 15 people on board perished.