Both are the youngest children of a significant heir to the throne and have been known for their naughtier, more lighthearted behaviour in opposition to their elder siblings.
In the 1980s, a young Prince Harry was often photographed sticking his tongue out at events and causing mischief, much like Prince Louis did in the royal box last weekend.
The Duke of Sussex was encouraged by his beloved mother Princess Diana, who said he could be naughty as long as he was “discreet”.
In the documentary, ‘Diana, Our Mother: Her Life and Legacy’ commemorating the 20th anniversary of her death in a Paris car crash in 1997, Harry revealed to viewers: “Our mother was a total kid, through and through…One of her mottos to me was ‘you can be as naughty as you want, just don’t get caught.’”
Royal expert Robert Jobson shared a story from royal protection officer Ken Wharfe, who worked with Princess Diana in the 80s and 90s.
He wrote in his book ‘William at 40: The Making of a Modern Monarch’: “The brothers, still just eight and six, were having an argument on the back seat when Harry suddenly burst out: ‘You’ll be King. I won’t—so I can do what I want!’”
Mr Wharfe later added: “The Princess and I just looked at each other, a little shocked by what he had said.”
While both Prince William and Prince George have been groomed to be King since birth, their younger brothers have had a less certain future within the Firm.
When Prince Harry was born he was third in line to the throne, and although it was unlikely he would ever be King he was in a position of seniority within the Royal Family.
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He later clarified what he meant: “Trapped within the system, like the rest of my family are. My father and my brother, they are trapped. They don’t get to leave.”
As the Queen gradually reduces her workload and talk of a “slimmed down” monarchy gains traction it is possible that Louis could take on a prominent position as a working royal.