A tiny detail in a little boy's eye led to a shocking diagnosis after his mum noticed him behaving unusually while he watched television.
And despite Naomi Jepson's concerns about her son Oliver, six, being dismissed initially by hospital staff, they eventually learnt he had an undiagnosed and aggressive brain tumour.
Ms Jepson, from Killarney, NSW, first grew concerned at the start of this month when she saw Oliver covering his eye while watching TV.
He told her he had double vision so she rushed Oliver and his sisters, four and one, to the optometrist. But with no appointments available, they had no choice but to return home.
Mum's concerns dismissed
But the next day, a glance at her son through the rearview mirror of her car is what ultimately led to the life-changing news, that her son had Rhabdomyosarcoma (RMS), a rare brain cancer formed in the soft tissue.
The mum of three was driving from Wyong to Lismore where her husband, the kids' dad, had been staying for work.
"On the drive up Oliver's eye turned slightly inwards, he started seeing double and was suffering from occasional headaches that left him holding his eye," Ms Jepson revealed on Facebook.
Although she "wasn't too worried" she quickly called the national medical hotline Healthdirect for some advice.
"They said I should get him straight to emergency to be checked over because it could be neurological," Ms Jepson said told Nine News.
But when they arrived at the emergency department in Lismore's public hospital, they waited hours before being turned away. Ms Jepson was told it "wasn't an emergency" and was told to "go to the GP instead."
Frustrated and worried, the mum eventually phoned another optometrist who "did all the tests," but when his eyesight appeared normal they too feared it could be neurological.
Devastating cancer diagnosis: 'No words'
A few days later, an MRI scan revealed devastating news. Doctors had found a large lump on his brain.
Oliver was flown from Lismore hospital to Sydney Children's Hospital. Once there, the family was told the tumour was inoperable because of where it is placed.
The only option is chemotherapy which young Oliver will endure for the next 12 to 18 months.
The tumour had been present for about three months, the devastated parents were told. But it only took days to get a diagnosis after first noticing his symptoms.
"It has been a rollercoaster of a week, I'm sitting here bawling my eyes out thinking how on earth has this become our reality," Ms Jepson wrote on a GoFundMe page set up for her son.
"There are no words to describe the pain Nathan and I have felt, for how scared we are or for how much we love our Oliver."
Mum's warning to others: 'Trust your gut'
Ms Jepson said she feels "terrified and helpless" not knowing what will come.
"He has about an 80 per cent chance of survival, but [doctors] won't know if they've cured it for at least one to two years," she told Nine News.
Ms Jepson and her husband Nathan have both quit their jobs. They've started an online fundraiser which has so far raised over $19,000 to help with their medical and living costs.
Ms Jepson is grateful for the advice she received from Healthdirect, which ultimately led to Oliver's diagnosis.
She's now urging parents to "trust your gut".
Do you have a story tip? Email: firstname.lastname@example.org.