"You could only see it in photos initially but it started getting bigger in time.
"Every time he had his vaccinations I would ask the GP to look at it as well and they just kept disregarding it."
Ms Rao said she was repeatedly told by doctors who examined her son's eye that the discolouration was "probably just nothing" and "would go away".
"One doctor said it was a beauty spot," she said. "The doctor was so confident, I didn't think there was any point pushing that further. But later on I still felt something was wrong."
It wasn't until the family went on a holiday to India in 2013 they finally received the answers they needed to help Aayaan.
"We took him to an eye specialist who said straight away something wrong and sent us to a bigger city with bigger instruments that could detect better," Ms Rao said.
Aayaan was diagnosed with retinoblastoma - a form of eye cancer which affects children under five years of age. It was discovered that a tumour was growing on his retina which had detached from his right eyeball. The tumour was sitting dangerously on his optic nerve, connecting to his brain. The decision about what to do next was an easy one, according to Ms Rao.
Aayaan had surgery at a hospital in Bangalore, in south India, followed by chemotherapy treatment before being given a clean bill of health. His tears and bone marrow were collected during the procedure for research.
"Within one week of seeing a specialist we moved to Bangalore and he had his right eye completely removed within 10 days of everything,' Ms Rao said.
"The doctor gave us a choice of going through chemotherapy first but we knew even if he was fine after that there was a chance of it coming back.
"It would have been life threatening if left undiagnosed. We wanted to take no chances."
Aayaan is now a happy, healthy and cancer-free Year 1 student who has adapted to life with only one eye "very well", according to his mother.
"He's very cheeky, he's absolutely very cheerful, a happy little boy, who is very active," Ms Rao said. "We were so lucky that we noticed the white reflection in his photos.
"I'm very scared to think of what might have happened if we didn't."
Ms Rao and her husband Alok said they wanted to speak out about their son's experience to make other parents aware of retinoblastoma.
Melbourne Royal Children's Hospital orthoptist and retinoblastoma care co-ordinator Sandra Staffieri said "not many people are aware of the signs to look out for" because retinoblastoma was a rare form of cancer.
"If you notice an eye has a white pupil in a photograph this indicates that the flash is
reflecting off something inside the eye," she said.
"If you notice a child has a turned eye or a white pupil in a photo it is very important to have the child's eyes examined by an eye doctor within 48 hours. Early detection is the absolute key to ensuring that a child has the best possible chance of surviving retinoblastoma and retaining their full vision."
Associate Professor Mark Daniell, president of the Royal Australian and New Zealand College of Ophthalmologists (RANZCO), said retinoblastoma is the most common eye cancer found in children. It affects approximately one in 15-20,000 children worldwide.
"Early diagnosis is key to ensuring a child has the best chance at surviving retinoblastoma and so recognising the warning signs, such as a white pupil reflection in a photo, is very important," Prof Daniell said.
The survival rate is 98 per cent for children who are diagnosed with retinoblastoma in Australia and New Zealand, according to RANZCO.
