Based on her story that she didn't start with him until after Harry was born? The testimony of the adulteress is not exactly probative on the issue.
Or are you suggesting that we should be looking at one of the other lovers. He wasn't exactly the first, was he?
I am suggesting that from the time of Harry’s birth until four years ago, i.e. almost 30 years, Harry was third in line to the throne, based on bloodlines. Do you seriously think for one minute that if there was any possiblility that he is not Charles’ biological son, the royal family wouldn’t have bothered to get a DNA test? Be real.