A girl aged eight is thought to be the youngest person ever to be affected by breast cancer.
Chrissy Turner, from Utah state in the US, discovered a lump on her chest in October.
Her parents are no strangers to fighting cancer.
Dad Troy Turner, a military veteran, was diagnosed with non-Hodgkin lymphoma, a blood cancer, in 2008. He underwent chemotherapy, but the disease came back in 2011.
His wife, Mrs Annette Turner, had cervical cancer, but is now free of the disease.
Chrissy's mother told ABC News that it was the girl who first found the tumour.
“She came to us on a Sunday afternoon. She said, ‘Mommy I have been scared and I have this lump.' It had been there for a while.”
"I was in shock," Mrs Turner, a personal trainer and holistic life coach, told ABC about her daughter's Nov 9 diagnosis.
"No child should ever have to go through cancer," she added.
To her parents' horror, tests revealed Chrissy was suffering from a very rare form of breast cancer called secretory carcinoma. This type of the disease affects just one in a million people diagnosed with the disease - and Chrissy will now need to undergo a mastectomy.
"I was scared the first time I knew about it," Chrissy said. "But I knew I could fight it off and I hope that I can fight it off."
She will undergo her surgery at the Huntsman Cancer Institute, Utah.
Although the tumour is rare, doctors at the Primary Children's Hospital in Salt Lake City told ABC they are confident that it can be removed.
"It is very treatable," Chrissy's physician Dr Brian Bucher told ABC.
"Chrissy will need to undergo a simple mastectomy...to remove all the remaining breast tissue to prevent this cancer from coming back."
In the meantime, friends of the family have started a Go Fund Me campaign to raise money for medical bills.
So far, they have raised more than US$25,000 (S$30,000), about a quarter of their target of US$100,000.
"We're just going to keep fighting," her mother said. "Doing everything we can to smile every day and laugh every day and carry our heads high and do our best to overcome this."
For more information on Chrissy's fight against cancer, go to https://www.facebook.com/ChrissysAlliance