When his 23-month-old daughter fell asleep in a swing, Dave Fletcher thought it was a heartwarming childhood memory, so he snapped a picture.
Sadly, just a few weeks later, Mr Fletcher and his wife Vicky were told their daughter had leukaemia.
Since the diagnosis, Izzy has undergone 570 doses of chemotherapy and is receiving maintenance therapy in an attempt to stop the cancer returning.
Mr Fletcher told Yahoo News that "she was swinging away" when he took the photo.
"I turned around and she had dropped off. I didn't think much of it. I thought it was a cute moment and took a picture of her as you do.
"It was only afterwards I realised it was all part of the symptoms, and what I'd captured was her displaying signs of something more sinister."
- Prime Minister pleads for more bone marrow donors after new mum relapses with leukaemia
- Kiwi family's financial struggle for medical care for sick daughter in Australia
"She had been tired, had a few colds and viruses and quite a bit of bruising on her legs. But we put all this down to normal childhood bumps and minor illnesses."
Mr Fletcher is warning other parents to be vigilant and on the lookout for the signs of the disease.
Izzy's father says his daughter has been forced to "grow up very quickly" in the wake of her diagnosis.
"[She has] been subjected to medicine she doesn't like but has taken everything in her stride so far," he said.
"The type of leukaemia she has has a better chance of recovery than some others. She is young which helps those odds."