The Duke and Duchess of Cambridge have reportedly broken royal protocol by flying together as a foursome instead of separately.
The royal couple have recently jetted off across the globe accompanied by their children Prince George, four, and two-year-old Princess Charlotte, but the family are reportedly not supposed to travel together for their public appearances.
According to The Sun Online the royal protocol states Prince William, 35, should not be on the same mode of transport as another heir to the throne, which his oldest child is.
However, this action should also apply for Princess Charlotte and her sibling, as they are third and fourth in line to rule Britain.
This traditional view was put in place many years ago when members of the royal family began to travel via aircraft because officials felt extra precautions needed to be taken to protect the King or Queen and their family.
A spokesperson for the royal family previously said: "While there is no official rule on this, it is something that the Queen has the final say on."
Meanwhile, the William and Catherine - who was formerly known as Kate Middleton before she married the royal - have put in place their own rules for their brood as they are believed to have banned their children from using iPads because they don't want their kids to become reliant on technology for entertainment and want to encourage them to use their imaginations.
A source previously said: "They're very much seen as Mummy and Daddy's toys, not for children.
"As two people who grew up without gadgets for entertainment themselves, William and Kate are firm believers in toys, outdoor play, and encouraging an active imagination. They're very much a normal family."