There is no question that Prince Harry's real father is Prince Charles but the rumors persist that Princess Diana got pregnant by somebody else and their offspring is Harry. There is nothing true to these speculations. Several theories about the supposed father of the Duke of Sussex have been debunked as well in the past years. 

One of the names that are being linked to the theories about the alleged real father of Harry is James Hewitt. He had an affair with Diana in the 1980s, around the time when Harry was born. 

Both the Princess of Wales and Hewitt admitted to the affair but said the affair happened after she had Harry. In the past interviews, Hewitt also denied that he is the Duke of Sussex's father.

Aside from having an affair with Diana, the other reason why Hewitt has been suspected to be Harry's father is that the royal has the same hair color as him: red. 

Another name in the conspiracy theories that Charles is not the real father of Harry is Mark Dyer. The Welsh Guards officer has been a close friend of Harry since he was young. Dyer even attended the Duke of Sussex's wedding to Meghan Markle. 

There was no evidence that Dyer had an affair with Princess Diana but his name has always among those who are suspected to be Harry's dad. Again, it is because of his hair color. He is also a ginger head. 

Gossip Cop pointed out that the hair color is a very absurd basis in proving Harry's real father. It has been proven that it's not a trait that has been passed down from Hewitt or Dyer. 

Diana's father, John Spencer, had red hair. Her brother, Charles Spencer, and sister, Lady Sarah McCorquodale, also has red hair. Louis Spencer, Prince Harry's cousin on his mother's side, is ginger-haired too. All of these only proved that the red hair is a very common trait in the Spencer family. 

Gossip Cop also noted that this trait is not only common to Princess Diana's ancestry but to Queen Elizabeth II's husband, Prince Philip, as well. The Duke of Sussex's paternal grandfather had a red beard in his younger days. The Duke of Edinburgh has not grown a beard since the 1950s, so many don't know that he has some red-hair genes too. 

In 2016, Vanity Fair published a photo of the young Duke of Edinburgh that showed his resemblance to Prince Harry. In the photo, Philip is seen with the same pale blue eyes, red beards, and mischievous smiles just like Harry.