The Royal Family are lucky enough to jet off frequently as part of their royal duty. However, when doing so they are subject to a number of stringent rules that your average traveller may not ever face.
This time, they also took their daughter, Princess Charlotte, with them.
While the change to the rule may just be the case of the Royal Family moving with the times, it has also been suggested that taking one flight has a direct link to keeping costs low.
Ahead of their New Zealand and Australian tour, in 2013 a royal aide told The Mail on Sunday: “It’s a long way to fly, and there’s a cost implication if they travel separately.”
However, as the children grow older, there is speculation as to whether Prince William and Kate will reintroduce the rule.
Some sources suggest Prince William and his children will fly separately once they hit 12 years of age.
None of the Royal Family has spoken out explicitly on the topic yet, but the younger members are increasingly modernising traditions.
In years gone by, Queen Elizabeth II and her children opted to fly privately on the Royal Plane.
Yet, as the world pushes towards more environmentally friendly travel, the younger royals have changed the way they fly.
This included travelling on commercial flights alongside regular travellers.
Prince William has been known to fly on British Airways and has even been spotted on budget-carrier Ryanair.
In 2015, passengers spotted the heir to the throne on-board a Ryanair flight from Norfolk to Scotland.
A fellow flier snapped a photograph of the moment they snooped him out, explaining to The Sun that upon landing they “realised the Prince was onboard”.
They explained: “I never expected to see him on Ryanair, but its refreshing to see a member of the royal family take a cheap flight.”