PUBLISHED: 11:34, Fri, Oct 2, 2020 | UPDATED: 11:35, Fri, Oct 2, 2020
Royal children must travel abroad with their parents when on royal tours. Prince George and his sister Princess Charlotte are already no strangers to the jet-set lifestyle, despite only being seven, five and two-years-old respectively.
Prince George embarked on his first Royal tour to New Zealand in April 2014 aged just nine-months-old.
Meanwhile, Princess Charlotte joined her family on tour to Canada in September 2016 when she was just one.
However, their youngest sibling Prince Louis has yet to hit this royal milestone.
When he does, though, he will be subject to the same fashion rule as his older siblings.
READ MORE: Royal travel: Prince Louis hasn't hit this huge royal milestone yet
Royal travel: The family arriving in Canada in 2014 (Image: Getty Images)
Royal travel: Prince George and Princess Charlotte seen in matching Burgundy (Image: Getty Images)
Whether in the UK or abroad, one royal tradition suggests that at public engagements brothers and sisters must match.
This means they tend to wear the same clothes if they are the same gender, or at least coordinating colours.
Though the Queen and her sister Margaret were often photographed in identical outfits, the younger royals tend to have gone for a more modern approach.
Prince George and Charlotte are often photographed in coordinating ensembles, however, they tend to be a little more unique.
Royal travel: Prince George & Princess Charlotte face strict rules [INSIDER]