SAN ANTONIO – Tiny, see-through fish might be the key to treating children with the rare muscle cancer, rhabdomyosarcoma.  

Local 13-year-old Kennedie Bailey, who just beat that cancer, saw the little zebrafish that may lead to a new treatment for other kids and prevent tumors from returning.  

It was Mother's Day 2017 when Kennedie's mom Lindsey found a big bump underneath her right ear. 

"It started with an ear infection," Kennedie said.

She had developed a rare muscle cancer they'd never heard of.

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"I couldn't even pronounce it," Kennedie said. 

It was Kennedie's upbeat attitude that got her through a tough year of treatment for rhabdomyosarcoma. 

"The radiation burned the inside of my throat. I couldn't go to school all 6th grade, so I was homebound. I had two teachers come to my house. They were the best teachers," Kennedie said. 

She's now been in remission for a year.

As well as she knows her way around a doctor's office, she's never been in a research lab and the first one she saw was extremely special to her.

It houses the very animals that are helping scientists find a treatment for the cancer she survived. 

"We are so excited that we get to see it in person," Lindsey said before they stepped into the lab at UT Health San Antonio's Greehey Children's Cancer Research Institute. 

The lab is filled with rows of tanks from floor to ceiling that house tiny zebrafish.

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"They're really tiny, so we can inject 1000 fish embryos a day and make tumors," said UT Health San Antonio researcher Dr. Myron Ignatius. 

Ignatius works with the zebrafish every day. 

"We take a human gene that causes the cancer and put it in the fish, it looks exactly like the human disease," he said. "So the questions we want to know is, how do these tumors form? What drives them? Are they stem cells and can we treat them? Can we find a drug that can limit tumor growth or reduce tumor growth?"

He said the small clear fish offer the extremely rare ability to watch tumors grow in real time. 

"That's a tumor in the belly," he said, showing Kennedie the fish with swollen bellies. 

"if you put it under the microscope it will actually glow green," Dr. Ignatius explained. 

The fish injected with florescent color light up when put under a blacklight, so the tumor can be seen more clearly. 

"We've identified critical genes that drive this disease. And one of the genes we study is a gene involving relapse," Dr. Ignatius said.

He said 20-30 percent of the time, rhabdomyosarcoma tumors come back. 

"If the tumor comes back there is no treatment," he said. "So we're going to find out one gene at a time, how do these genes cause cancer? Do they get mutated? And can we treat them?"

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The goal is to shrink or eliminate the tumor with treatments they have in the lab, and if that works they could try the treatment in a clinic setting. 

It's a goal Kennedie and Lindsey hope the research team can reach. 

"For other kids who get it there's more research, more treatments more options," Lindsey said. 

As for Kennedie, she's wasting no time. She has packed her 8th grade schedule with all AP classes, National Honors Society, PALS mentoring, basketball, and she wants to add year-round swim.  

She has more energy than ever and takes nothing for granted. 

Kennedie is currently getting scans every 3 months to make sure she stays cancer free. Eventually she'll only have to get those scans every six months.