MOBILE, Ala. (WKRG) — While they were on the front lines helping people battling COVID-19 in other parts of the country, little did they know, their 3-year-old was home in Mobile, fighting her own battle.

The respiratory therapists discovered their daughter had bone cancer.

Cecilia Tran never expected to celebrate her daughter’s fourth birthday in the hospital. Then, just six days before the celebration, little Scarlett Castanares and her parents are forced to face the unthinkable.

Diagnosis – Osteosarcoma. And chemotherapy is not beating this cancer. Doctors explain, they must amputate Scarlett’s right leg.

“It’s more common in teenage years and children who are growing rapidly, and it’s called a sports tumor,” said Dr. Hamayun Imran, M.D., USA Health Children’s and Women’s Hospital.

Tumors like this usually present as pain and swelling. The area affected typically feels warm for days.

Just months before, no symptoms for the active, athletic 3-year-old, bouncing around her living room, swimming, just being a kid.

“She loves to dance and take karate and swimming.” “Karate!” Yeah, karate right? How much do you like karate? So much,” said Tran and Scarlett.

But Scarlett’s ability to do the things she loved “so much,” changed in an instant.

“She was limping and when we asked her about it she said she got her foot stuck in the couch, and we didn’t think anything of it at first and then about a week passed by and it wasn’t getting better. So, we took her in to the pediatrician, and from there it just kind of catapulted into doctor’s visits and tests and things to figure out what was going on,” said Tran.

The symptoms started surfacing only in mid-February but quickly progressed. Scarlett quickly went from a walker to a wheelchair. At the time, Scarlett was staying with family members in Mobile. Her mother, working as a traveling respiratory therapist in Texas. Her father, also helping COVID patients, in Hawaii.

“It’s hard because with the pandemic going on for the last year or so, we haven’t really been able to be all together as a family, just because the risk and everything that comes with our job,” said Tran.

With Scarlett’s cancer diagnosis, Cecilia and her husband dropped everything, and flew home, and took Scarlett to St. Jude Children’s Research Hospital.

“We packed up the car and drove up here. It was early March and we’ve been here since,” Tran said.

Experts at USA Health treat Osteosarcoma, too. Dr. Hamayun Imran describes it as pretty common, but not in children Scarlett’s age. With aggressive treatment, Dr. Imran says, “The prognosis for localized osteosarcoma, the one that has not spread to the lungs or to multiple bones is really, really good. Close to 2/3, a bit more, can hope for a long-term cure.”

A long-term cure is exactly what Scarlett and her family are hoping for. For now, it’s more chemotherapy, and an indefinite stay at St. Jude. Their hope is, that by Scarlett’s 5th birthday, her life will be much different.

A Go Fund Me set up to help Scarlett’s family, now that her parents are out of work, and the bills aren’t stopping. You’ll find it here: https://www.gofundme.com/f/help-scarlett-fight