I don't think that he has natural curly hair. Sometimes when your young your hair can be a different color when your younger and when you get older. I have seen babys with red hair but grew up with blonde hair or grow up with blonde hair and it goes from a caramel light brown color as they get older. Harry Styles has said to someone I thnk to a fan that asked about what curling shampoo or conditioner he uses and Harry Styles told him. I'm sure you could find out what type of hair products he uses at www.coolspotters.com and type in Harry Styles in the tab that says 'Search...' in the top right corner.