After taking her one-year-old kid to the doctor for a 'glow' in his eye, his mother learned he had cancer.

After undergoing multiple tests, Cillian Coyles was diagnosed with retinoblastoma, a rare kind of eye cancer.

The child has now lost vision in his left eye as a result of a tumor that physicians are attempting to reduce with chemotherapy.

Despite the difficulties, Leonnie Ord, his mother, claimed her son is still smiling, and the family is now raising cash for a cancer charity, according to the Liverpool Echo.

She initially observed the glow in her son's pupil in August, but because it came and went, she assumed it was merely a reflection of the light.

However, it began to gain prominence and popularity in October.

Despite enduring grueling therapy, the happy-go-lucky tot, according little social worker Leonnie, is doing so with a permanent smile on his face.

After a "rollercoaster" few months, the 33-year-old is now advising parents to "know the glow," as being aware of this warning sign might save a child's sight - and, eventually, their life.

Cillian is seen in September with a slight white reflection in his eye, but images taken three months later with flash show an apparent circular glow surrounding his pupil.

"Essentially, that happy, smiling photo of him covers a secret that may be deadly if not found in time," Leonnie, from Hebburn, Tyne and Wear, said.

"If you see anything unusual in your child's eye, you should have it looked out. Don't be afraid to inform a parent if you observe problems with your friend's child's eye or if you see a snapshot on Facebook." Because as a parent, you'd rather be scared for a week waiting for an appointment than it being too late and your child losing their eye or sight, or the cancer has spread. "Every change in the eye doesn't mean that it could be cancer, but if we'd spotted and got Cillian checked sooner, he could have potentially still had his sight in his left eye, we just don't know," says the doctor.

The loving mother of two claimed she didn't see the light in Cillian's eye until the weeks before his diagnosis, when it became more noticeable.