BOULDER, Colo. -- Like most 12 year olds, Andrea Rodriguez likes sports and playing games.

Late last year though she began complaining of leg pain.

Eventually doctors would say the words no parent wants to hear -- it was cancer.

"At this moment, our world crashed," said Gonzalo Rodriguez, Andrea’s father.

He said it got worse when doctors at National Institute of Pediatrics in Mexico City told them Andrea had tumor so large there was nothing they could do.

"The doctor told me, ‘Please take your daughter, go home and wait until she dies,' " an emotional Gonzalo recounted.

It was something the family of four could not do. Friends and family helped them research treatment options around the world. But with very little money and no insurance it didn't look good until they heard from an oncologist at The Children's Hospital in Aurora.

“The doctor said, ‘let's not worry about that; the expenses, let's see her,’ " explained Yolanda Berea, a friend of the family who lives in Niwot.

A spokeswoman from The Children's Hospital declined to comment on specifics regarding Andrea's case.

"We have financial counselors working with each and every family to meet their financial needs," Natalie Goldstein told 7NEWS last week.

Gonzalo, who was working at a real estate professional near Mexico City, immediately sold his house, the family car and many possessions to bring Andrea here along with his wife, Lorena and two sons, Sebastian, 9, and Juan Pablo, 4.

He told 7NEWS the family came to the United States on a six-month tourist visa.

Since arriving in March, Andrea has had surgery plus chemotherapy. Part of her hip and her entire right leg have been removed.

"Children's Hospital is a miracle place," Gonzalo said.

With her father translating, Andrea told 7NEWS she has good and bad days, but is excited about getting a prosthetic leg.

Gonzalo said it is her strength that keeps him going.

"She's stronger then me, I don’t need to say anything to her. She tells me all the time the things I need to survive," he said. He also explained that he was moved by his daughter’s behavior prior to her leg amputation surgery.

“On the way to the hospital she sang,” he said.

Their fight continues. More treatment and surgery is needed as the cancer has metastasized in her lungs.

Gonzalo said they've been told 20 percent of people with this type of bone cancer, called Osteosarcoma, survive.

"We try to think all the time about life; we are fighting for life, not for death," he said.

Alongside the stress of Andrea’s health, also comes worries about finances.

Friends and neighbors have raised funds to help offset expenses.

The Winchester family in Boulder is currently allowing the family to stay in a one-bedroom apartment rent free.

Gonzalo said his worst fear is having to return Mexico. He said that would spell death for his daughter.

On Father’s Day, this father said he is full of hope and grateful for every day.

It is his daughter, he explained, who's helped him learn it's the best way to live.

"She teaches the whole family and all my friends about the happiness to live," he said.