Princess Charlotte and Prince George are set to be separated next year.
Royal protocol says that that heirs to the throne shouldn’t travel on the same flight from the age of 12, meaning from next year, 11-year-old George will not be permitted to travel with his parents and younger siblings, Princess Charlotte, nine, and Prince Louise, six.
George is Prince William and Princess Catherine’s eldest child and is second in line to the throne.
Prince William is first in the Royal Family’s line of succession and George’s younger sister Princess Charlotte is third.
The Prince and Princess of Wales broke the rules as their eldest children, Prince George and Princess Charlotte, joined them on their overseas tours.
Prince William and Prince George travelled together to Australia in 2014, Canada in 2016 and Germany and Poland in 2017.
William reportedly asked permission from the late Queen for George to accompany him and Kate on their visit to Australia and New Zealand.
Prince William travelled in a separate aircraft to the rest of the Royal Family when he turned 12, and will still never fly with the King.
Former royal pilot Graham Laurie previously told Hello!: “I know the King is trying to cut down cost and is aware of travel, but I think the safety side is still paramount.”
“Interestingly, we flew all four: the Prince, the Princess, Prince William and Prince Harry, up until when Prince William was 12 years old.
“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.
“What we did in the end, when William became 12, he would fly normally in a 125 from Northolt and we would fly the 146 or the Andover out with the other three on.
“Up until then, they probably thought it will be too much for him travelling on his own. But nevertheless, that’s what they did.
He added: “Our aircraft were painted red, white and blue… but they changed the colour scheme in 2002 to look more like a normal airliner.”
King Charles and Queen Camilla appeared to break royal travel protocol on their tour of the South Pacific in October.
The Royal Family is also supposed to travel British Airways, the flagship UK airline, while on tour.
However, the monarch and his wife were pictured leaving an Australian aircraft as they touched down in Samoa for the second half of their tour.
King Charles and Queen Camilla travel separately due to the Queen’s fear of flying, preferring to make more frequent stops than her husband.