The Royal Family must adhere to many seemingly strange rules in order to protect the royal lineage. One frankly unusual travel rule means often senior members of the Royal Family are not permitted to fly together unless they request permission directly from the Queen in advance. As the Cambridge family undertake a holiday abroad, many royal watchers are keen to know if the family were permitted to fly together or not.
Prince William, Kate Duchess of Cambridge and their three children were spotted at Heathrow Airport last week preparing for a half-term getaway.
The royals were seen outside the Windsor Suite, which is reserved for the Royal Family and other high profile celebrities, with Prince George, eight, Princess Charlotte, six and Prince Louis, three.
The Duke of Cambridge drove the family to the airport escorted by security.
Photographs taken at the airport showed the Cambridges wearing huge smiles as they unloaded their luggage outside the airport.
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This rule also means Prince Charles and Prince William are also forbidden from flying together – and Prince Charles cannot fly with his mother, the Queen.
In the past, the Cambridges have flown with their children.
Prince William was granted special permission from the Queen to bend these rules when his son was nine months old and the family travelled to Australia and New Zealand in 2014.
In addition, the Queen granted permission to the couple in September 2016, when they travelled with Prince George and Princess Charlotte to Canada.
The Cambridges flew together again during a tour to Poland and Germany in July 2017 – taking a total of three flights together.
However, the Cambridge couple has not always asked for an exception to the rule.
In December 2014, the Duke and Duchess of Cambridge travelled to New York.
Instead of taking their young son, he remained at home with his nanny and grandmother Carole Middleton.
Prince William is not technically allowed to travel with any of his children given their high position on the line of succession.
The Royal Family’s press office told Newsround: “They had to ask the Queen for permission, but she said yes.
“While there is no official rule on this, and royal heirs have travelled together in the past, it is something that the Queen has the final say on.”
The Queen has reportedly been inspired to allow the Cambridges to break this rule previously because aviation has become increasingly safe over the past several decades.
But it is likely to be a difficult decision for the Queen given her paternal cousin Prince William of Gloucester died during a plane crash.
He died, aged 30 in 1972, in an air crash while piloting his plane in a competition.