Apparently, so is Tyra Banks, host of America's Next Top Model! According to Debra Jaliman, M.D., assistant clinical professor at Mount Sinai School of Medicine in New York City freckling in the summer is a genetic tendency (Tyra, you can thank your mom for them). Melanocytes, melanin-producing cells located in the bottom layer of the skin's epidermis, cluster right under the skin in patters and get activated in the sun to form spots. Regardless of how cute they are now, it's important to prevent this activation as much as possible with SPF. "If you keep activating them, they will stay and not go away in the winter," says Dr. Jaliman.