However, it seems Prince Louis has escaped one of the rules Prince George followed rather strictly when he was younger.
It was also a rule that both Prince William and Prince Harry followed while they were young children.
You may recall, when George was a toddler, he was rarely seen wearing long pants and was mostly dressed in shorts. Even if it was cold, in which case he'd wear a pair of long socks.
On Christmas Day in 2016, George was seen leaving church wearing a long coat with shorts and socks underneath.
While on tour in Canada with his parents and sister, George once again wore shorts and to keep warm he wore a jumper.
However, Louis has been spotted wearing pants on the red carpet at a special pantomime performance of The National Lotterys Pantoland recently and again in the official Christmas card released by Prince William and Kate Middleton.
When William and Harry were kids there was a time when William was allowed to move into wearing long pants, while Harry still wore shorts.
Etiquette expert William Hanson has previously spoken to Harper's Bazaar about the reason this has always been a tradition.
He revealed it's a class marker and upper class boys usually graduate to wearing trousers from shorts at about age eight.
"It's a very English thing to dress a young boy in shorts," he said. Trousers are for older boys and men, whereas shorts on young boys is one of those silent class markers that we have in England.
"Although times are (slowly) changing, a pair of trousers on a young boy is considered quite middle class – quite suburban.”
Many situations where Louis has been seen wearing pants have been more relaxed family situations, which could mean the family prefer to take a more casual approach when it comes to protocol at home.
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