People only just realising what causes freckles and why they get darker

Have you ever wondered why some people get freckles while others don't? You're not the only one. Even some people who have freckles have no idea what causes them, or why they get darker over the summer months. Have you ever wondered why some people get freckles while others don't? You're not the only one. Even some people who have freckles have no idea what causes them, or why they get darker over the summer months.