Prince Louis is "not too dissimilar" from his uncle, Prince Harry.

Prince William and Kate Middleton's youngest child turns 6 on Tuesday. The youngest Wales, who made headlines for his cheeky behavior and playful antics in the past, has the same passion for rugby as his uncle Harry and this worries his mom as it is a physical sport, the Mirror reported.

"They're all enjoying it," Middleton replied when asked if her kids enjoyed rugby during a training session with the England Rugby team in 2022 ahead of the first Six Nations tournament.

"Louis is kamikaze," she added, referring to Prince Louis' style of playing.

"We're worrying about when he gets older, he'll be in the middle of everything," Middleton said.

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Prince William and Kate Middleton's Family
(L-R) Britain's Prince George of Wales, Britain's Catherine, Princess of Wales, Britain's Prince Louis of Wales, Britain's Prince William, Prince of Wales and Britain's Princess Charlotte of Wales wave from the balcony of Buckingham Palace after attending the King's Birthday Parade, 'Trooping the Colour', in London on June 17, 2023.
(Photo : ADRIAN DENNIS/AFP via Getty Images)

However, body language and behavioral expert Darren Stanton found more similarities between Prince William's youngest son and younger brother aside from rugby.

According to Stanton, Prince Louis is the "mischievous" and "rebellious" one like his uncle. He even warned that the youngest of the Prince and Princess of Wales' three children -- Prince George, 10, Princess Charlotte, 8, and Prince Louis -- was the "one to watch."

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Kate Middleton, Britain's Catherine, Princess of Wales and Prince Louis
Britain's Catherine, Princess of Wales (L) speaks with Britain's Prince Louis of Wales (R) as he sits inside a vehicle on a C17 plane during a visit to the Air Tattoo at RAF Fairford on July 14, 2023 in Fairford, central England.
(Photo : Chris Jackson/Pool/AFP via Getty Images)

"Prince George and Louis very much take on a similar dynamic to which Prince William and Harry had growing up," Stanton told Entertainment Daily in 2023 after observing Prince George and Prince Louis' behavior at King Charles' coronation.

"George is very much the older brother, always looking out for Louis and Charlotte -- I think he tries to emulate his dad, and it's already clear that he's going to be the serious one out of the two brothers."

Some fans said Prince Louis reminded them of Prince Harry when the latter was younger because he was as cheeky. For instance, the Duke of Sussex was also caught on camera sticking his tongue out in public with Princess Diana.

Stanton acknowledged the comparison between Prince Louis and Prince Harry.

"Prince Louis, as we saw on the balcony, trying to play the piano -- he's undoubtedly the more creative one, the more mischievous one, the more rebellious one and the one to think outside of the box, not too dissimilar to Harry," Stanton continued. "Louis is certainly going to be one to watch."

Prince Harry has seemingly cherished his youngest nephew. In 2018, the Duke of Sussex gifted Prince Louis a first-edition copy of "Winnie-The-Pooh" worth $9,800 on his Christening, The Sun reported. The book was reportedly inspired by his late mom, Princess Diana.

Tags: Prince Louis Kate Middleton Prince William Prince Harry