runs out. We move on next to a story of modern time and friends who come to Rees sue. A mother posted a picture of her daughter, moments later, she was seeking medical help. What a friend saw that... See More
runs out. We move on next to a story of modern time and friends who come to Rees sue. A mother posted a picture of her daughter, moments later, she was seeking medical help. What a friend saw that doctors had missed. Reporter: 3-year-old Riley Taylor doesn't shy away from the camera. But when her mom posted this photo of the toddler, she got much more than a few likes. It was just a pretty picture of her. I thought it was really sweet. Reporter: Taylor's friend Stacy Carter saw more than just Riley's adorable smile. She noticed this white glow in her left eye and thought it could be a symptom of a rare disorder. Stacy says her friend's son had an eye disease with the same symptom. I immediately sent her a message and said "Hey, it could be nothing, or, you know, there could be something really wrong with Riley's eye." Reporter: Three doctor visits later and one week later, the toddler was diagnosed with coat's disease, a disorder causing blindness. It comes from an abnormal development of the blood vessels behind the eye. Reporter: One symptom, abnormal reflection of light, say from a camera flash, which is what caused the white spot in Riley's eye. Without that flash, her eye looks completely Normal. And Riley's parents say they never saw anything unusual. Coat's disease is extremely rare and overwhelmingly affects boys. Doctors say it's normally not detected in children until it has progressed much further, affecting both eyes. But, thanks to Taylor's keen-eyed Facebook friend, in Riley's case, it was diagnosed early. And after two surgeries, doctors say they have saved the vision in her left eye. We wouldn't have caught it at all if someone didn't bring it to our attention. Reporter: One little girl saved, thanks to a share.
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