Transcript for How One Cell Phone Photo Saved This Toddler's Life

Today's hot button There it is. One mom's life-saving discovery. She snapped a photo of her son. What she found saved her son. When Julie Fitzgerald took a snapshot, she had no idea what the photo would ree veal. Something in his eye caught her eye. She knew there was a serious problem. Playing with his older brothers, 2-year-old Avery looks like the picture of health. It was a picture that would reveal he was battling a silent killer. My world completely shattered. It literally changed in the blink of an eye. Reporter: It all started when Julie and Patrick Fitzgerald noticed unusual spots on Avery's eye. I had this gut feeling in my stomach that something was wrong with his eye. Reporter: Still, she brushed off that queasy feeling until she stumbled upon a story on Facebook. How a white glow in photos could signal bigger problems. She snapped in photo. It revealed the telltale white in his eye. You have to see the doctor right way. If you miss that sign, it may be fatal. Reporter: They acted immediately. Within days of taking that photo, their suspicions were confirmed. He had tumors covering 75% of his eye. Though the toddler's eye had to beremoved, doctors say it was caught just in time. If we did not get this eye out, the cancer would spread to his brain. Reporter: This is not the first life saving snapshot. Just last month, another mom in Arizona took action after seeing the very same glow in her infant daughter's eye. As for Avery, he's now cancer-free. Thanks to a mother's independent wigs. Our lives went from Normal to cancer. To a cancer survivor. It turned out to be our worst nightmare. But, it saved our son's life. You're okay. The fitzgeralds are not completely out of the woods just yet. They have to find out if Avery will have to undergo chemotherapy. Dr. Besser says this type of cancer is very rare and usually presents its before the age of 3. Parents, you have to look for science of the vision problems. Next up on the heat index, one woman's dramatic weight loss

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