Grace Freeman’s parents must be very happy that they put a photograph of their daughter on the popular website, Facebook. According to The Daily Mail, the image of the two-and-a-half-year-old girl helped a nurse discover that the toddler was afflicted with eye cancer.

Nicola Sharp was surfing through Facebook when she came across a picture of her friend Michele Freeman’s daughter, Grace. In the image, the flash had caused the little girl’s eyes to take on a peculiar tint. While the toddler’s right eye appeared red – a common occurrence in flash photography – her left eye was white in color.

Nicola Sharp is a pediatric nurse, and knew that a white pupil in a photograph could be an indication of eye cancer. She quickly contacted Michele, who took Grace to the doctor and discovered that the toddler did indeed have two tumors.

Though Grace’s condition, known as retinoblastoma, may have caused her to lose sight in one eye, if it weren’t for Sharp’s quick reaction, the cancer could have spread and become fatal.

According to the American Optometric Association, school-aged children should be taken to the doctor at least once every other year in order to diagnose any vision problems that may not be noticeable to the untrained eye. Children wearing glasses should go more often as their eyes are constantly growing, and their prescription may change.