"Trust a momma's gut."

That is the advice that Julie Fitzgerald, a mom of two boys, has for other moms when talking about kids and health. Fitzgerald speaks from experience: She recently used a cellphone photo to diagnose her son's eye cancer — and in doing so she saved his life.

A few months ago, Fitzgerald said she noticed something odd when she would look into the eyes of her 2-year-old son, Avery. Not all of the time, but every now and again, in a certain light, she felt like she could see spots in his left eye.

Like most modern moms, Fitzgerald went straight to Dr. Google to understand what she was seeing. She came across a story about a woman who saw a white eye in photos of relatives instead of the normal red eye and ultimately learned that it was caused by cancer.

Fitzgerald talked it over with her husband, but he told her not to worry. Still, she couldn't let it go.

"I took a picture, and I did not want to take the picture because I had this dreaded feeling in the pit of my stomach and I took the picture and boom. His whole pupil was just white and that's when I knew," Julie told WREX news.

Fitzgerald took Avery to a doctor and received the bad news. Avery had a cancer of the eye called retinoblastoma with tumors covering 75 percent of his eye. To save his life, Avery's eye had to be removed.

"If we did not get this eye out, the cancer would spread to his blood and to his brain," Fitzgerald said. "Our lives went from normal to cancer to a cancer survivor in three weeks. It turned out to be our worst nightmare, but it saved our son's life."

In the end, Fitzgerald's husband has one piece of advice for other dads out there:

"Listen to your wife."

Smart man.

Now, before you freak out and start snapping pictures of your kids, here's more information about retinoblastoma and how it is diagnosed:

Retinoblastoma is a very rare cancer of the retina. It occurs in only about 250-300 kids in the U.S. each year. One of the main symptoms of the disease is the "cat's eye," or yellowish-white glow that can be seen when a light — or camera flash — reflects off the back of the eye. Other symptoms include poor vision, pain in the eye, or eyes turning inward or outward.

Again, this condition is very rare. But if you are concerned, take your child to her health care professional right away.

Remember Julie Fitzgerald's advice: Trust a momma's gut.

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Mom detects son's cancer with cellphone photo
Julie Fitzgerald's motherly instinct led doctors to a quick diagnosis that saved her son's life.