Looking at Diana's older sister Lady Sarah McCorquodale, it's clear that Harry has inherited his hair colour from his mother's side.
But while examining the royal photo albums after the sad news of the passing of the Duke of Edinburgh back in April, we've noticed that the Duke of Sussex also bears an uncanny resemblance to his grandfather on his dad's side of the family.
WATCH: Prince Philip's sweetest family moments
Photos of a young Philip show a striking similarity between the two. Harry appears to be a carbon copy of his grandfather, bearing the same piercing clear eyes, strong brow, slender nose and thin lips.
Harry started showing a likeness to the Duke of Edinburgh from a very young age, when he was a teenager and shared the same mannerisms and expressions.
Harry started showing a likeness to Philip from a very young age
Harry followed in Prince Philip's footsteps by serving in the armed forces for ten years and was deployed to Afghanistan twice. His grandfather boasted a formidable military career in his time.
At 21 years old, Philip was one of the youngest first lieutenants in the Royal Navy and went on to serve during World War Two. He grew a full beard while out at sea – a far cry from his normally clean-shaven look.
Philip sported a beard when he was away in the armed forces in his younger years
Harry, meanwhile, has been sporting a beard since 2013 when he completed a charity trek to the South Pole with Walking With The Wounded. The Queen reportedly told him to shave it off, with an insider at the time saying: "She doesn't mind royal men growing beards when they are away in the armed forces or out in the wilds like Harry was in the Antarctic, but she expects them to be clean-shaven when they get home."
Harry shaved off his beard in the New Year, despite his girlfriend of the time Cressida Bonas reportedly liking the look. But after the Prince left the army in June 2015, he went back to growing a beard and has kept one ever since.
Of course, the similarities don't end there. Harry and Philip also shared a wicked sense of humour. Princess Diana's son is well known for his cheeky personality – especially when he teams up with big brother Prince William. The Duke of Edinburgh, meanwhile, had a reputation for his sharp one-liners; it was previously revealed that the Queen was advised not to marry him because courtiers thought he was too funny.
Redhead Lady Sarah McCorquodale, Diana's sister, used to date Prince Charles
Harry, however, has also been likened to his mother's side of the family, the Spencers, in particular his aunt Lady Sarah McCorquodale and his uncle Earl Spencer. He is believed to have inherited his flaming ginger hair from Diana's side – the comparison can easily be made with redhead Lady Sarah, who coincidentally dated Prince Charles in her younger years before he moved on to court Diana.
Harry has also been likened to his uncle Earl Spencer
And while Harry and Prince Philip appear to share the same nose, other royal fans are convinced the Duke of Sussex has taken after his uncle Charles, Diana's younger brother, who also sports a very similar slender nose.
Harry flew in from the US to attend his late grandfather's funeral on 17 April and walked in the procession alongside Prince William and their cousin, Peter Phillips.
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