Brodie Donegan was 36 weeks pregnant when, in just minutes, her family's life changed forever.
At a routine ultrasound, everything looked "totally fine until the last minute" and her baby moved into a different position.
"And they [the sonographer] said, 'Oh, we'll just measure his head' and that's when they sort of went, 'Oh, hang on, I can see something I can't ignore, I've just got to go and speak to somebody about that'," Donegan told news.com.au.
Despite doctors assuring her it was probably fine, the mother-of-three "felt like something was wrong".
"And because we'd lost a baby previously, we just felt there was more that you could do for them once they're out," she said.
"We were just, you know, so worried that it would just continue to get worse. So we just wanted to get him out as soon as possible, just so everyone could start working on him and figuring out what was wrong."
By the time Nixon was born just over a week later, the lump above his right eye was 5cm long and 3cm high.
It would take an invasive, five-hour biopsy when he was just four days old to figure out a diagnosis.
"Because nobody could come up with an answer to what it was, they felt that it was the only way to go," Donegan said.
"It was only supposed to take about an hour, and it took over four hours because he had to have a few blood transfusions and they said that once they did the first biopsy, they realised that it was necrotic, so they had to make a larger incision."
As soon as she heard the word "necrotic", Donegan began to fear the worse.
"I'd only ever heard that word associated with tumours, so I went down that path. They told me not to, but at that point we were just getting more and more anxious day-to-day to get the results."
When she and her partner Nick were told, two weeks after their little boy was born, that he had an extrarenal rhabdoid tumour – an extremely rare and aggressive form of cancer – she said she "wasn't surprised".
"But it wasn't what I wanted to hear. We just felt a bit hopeless. We did ask them not to give us any specifics, and not to tell us how much of a chance, or what sort of prognosis he had," she said.
"All they said was that it was not worth not trying."
Nixon went into surgery straight away to have a central line inserted, and at just two and a half weeks old, began the first of 10 rounds of chemotherapy.
"They couldn't remove the tumour until it had shrank, and they didn't know if it was going to shrink, so it was a bit of a nervous start," Donegan said.
"We were literally just going day by day, but we did start to feel some relief, some hope, as the days and weeks went on, as we could see the tumour shrinking. I think one of the benefits of it being on his head is you actually see it – it looked like it was almost melting away.
"And it was only really when, because I took a lot of photos, when we looked at photos and because I put beanies on him, and I noticed that the beanies weren't as tight."
After his fourth round of chemo, at three and a half months old, the doctors decided Nixon was strong enough for surgery. By that point, the tumour had shrunk from the size of an adult fist to just a "little bump" on his head.
The surgery was a success in removing the cancer – and after another six rounds of chemo, as well as multiple procedures and the insertion of skin expanders to heal the wound on his scalp where the tumour had been – Nixon was declared NED (no evidence of disease) in early 2016.
Nearly five years later, Donegan describes her son as "strong-willed, stubborn and adventurous". And while he'll start kindergarten next year, she said for a long time after his diagnosis she wouldn't let herself imagine a future like this.
"I was hoping that we'd kind of end up getting back to a normal life at some point, but at the same time I almost didn't want to hope and be disappointed," she said.
"I think the first few years, I was terrified of planning ahead and then having my hopes dashed. I don't think I breathed for two years, I was just constantly in a state of survival."
Now, the family are focused on sharing Nixon's story to help raise awareness about childhood cancer with the Children's Cancer Institute.
"Nick and I are just really keen to support the Children's Cancer Institute because there needs to be more research, and we just need to save more kids. It's heartbreaking watching them go through it," Donegan said.
"We're really lucky that every decision that's been made has been the right one for Nixon and he's done really well. But we've also seen a lot of children that haven't, and we know a lot of children that didn't make it. So for us, it's so important to really push the research. I feel like it's almost our responsibility to try and help."