What's the best part of a royal tour? Seeing Prince William, Kate and their adorable 2 kids walking arm in arm. Some of the sweetest moments happen when the tots are getting off airplanes with their mom and dad. This includes Charlotte's first attempt and at a curtsy and George's adorable post-flight face.
What many don't consider is that when the family travels together, Prince William is actually breaking a very important royal protocol.
Though it seems like standard practice for families to travel together, though not official, those in succession of the throne are supposed to travel separately, should anything happen during their travels the lineage would stay in tact.
That means Prince William, who is second in line to the throne after his father Prince Charles, should not be travelling with his son, Prince George who is third in line. If we are to get technical, that also means that Prince George, and Princess Charlotte shouldn't be travelling together either, because she is fourth in line to the throne.
So how is he able to get around these rules so that his family can travel together?
"While there is no official rule on this, and royal heirs have traveled together in the past, it is something that the Queen has the final say on," a spokesperson for the royal family told BBC.
The 35-year-old dad had previously asked the Queen for permission to travel with Prince George on a royal tour through Australia and New Zealand in 2014 when his son was less than a year old.
The budget-conscious royals are also known for liking to keep costs down whenever they can.
"It’s a long way to fly, and there’s a cost implication if they travel separately," an aide said about their trip "down under".
Most recently, the family traveled to Poland and Germany in a Royal Tour, and the children accompanied their parents to Canada last year.
Previous generations of the Royal Family, including the current Queen, typically traveled without their children, who were left behind with governesses.
Though it's no surprise that the Duke and Duchess of Cambridge will break Royal protocol for the sake of their family, they're known for doing things their own way.
Prince William recently hugged a victim of London's Grenfell Tower fires, which breaks etiquette stating that "members of the public are only allowed to shake hands with the royals."