NORTH TEXAS (CBSDFW.COM) – Pediatric cancer is the number one cause of death by disease in children.

Consider this: of the billions of taxpayer dollars that go to cancer research, just four percent of the federal funding goes to all pediatric cancers, combined.

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One young leukemia survivor from North Texas is determined to change that statistic.

Eleven-year-old Sadie Keller is focused.

Sadie Keller (CBS11)

“I’m making a fluid art painting. It’s pretty much just thinning down paint and putting them all together in cups,” she explains.

The painting she’s making in her home studio may one day hang in a collector’s home. Money from the sale will raise awareness for pediatric cancer.

“[People] are just saying, ‘What you’re doing is making a difference’,” Sadie says.

Sadie did not choose this cause at random.  She says it chose her.

She turns to show two other paintings she made of a different style. One, of a girl with angel’s wings, standing with her hand in hand. It is her friend Sadie, who lost her battle with cancer.

The other painting is of a little girl wearing a headscarf and a black dress, laying down on a bed. This painting is a self-portrait. Sadie is the girl going through chemotherapy.

“It is a picture of me laying in a hospital bed. These paintings are so special to me. I’m not ready to sell these originals,” she explains.

February 25, 2015 was the day then-7-year-old Sadie was diagnosed with Acute Lymphoblastic Leukemia.

“I was just so scared and nervous with all the rest of my family and I didn’t know what to expect at all,” Sadie remembers.

She did know, if she was feeling this way, other kids were, too.

Early in her treatment, Sadie began sneaking into her mom’s closet and recording videos with an iPad. In each video, she speaks directly to the camera with confidence and truth. Her audience? Other children with pediatric cancer.

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“There’s nothing that you do, that you ate, breathe, that would make you get leukemia. It just happens,” says Sadie, in one recording.

The videos have been widely shared on social media, and that was just the beginning for this young advocate.

As she fought for her own life, Sadie continued to give.

She collected toys for young patients at local hospitals at Christmas. Her foundation, Sadie’s Sleigh, has done this every year for three years. This past holiday season alone, they gathered 10,000 toys.

There are also parent packs: gift cards for food and essentials given to moms and dads of kids with cancer. Milestone gifts: cool presents she hands out to patients when they reach important milestones in their cancer journeys. Her painting sales help fund these gifts through the Sadie Keller Foundation.

She’s also a lobbyist for pediatric cancer research and awareness, taking her story to Capitol Hill.

She’s making a difference there, too: Sadie was front and center when President Trump signed the STAR Act in June.

The STAR act is the most comprehensive childhood cancer legislation ever taken up by Conress.

“I also want to commend Sadie Keller for her leadership,” President Trump said, during the signing of the bill.

Sadie Keller with President Trump (White House Photo by Shealah Craighead)

Knowing what a small percentage of federal money goes to children’s cancer research is frustrating, Sadie says. “I was so upset [when I heard that], because people think childhood cancer is rare, when it is not.”

Sadie Keller knows their lives are worth more than four percent. She remembers her own two-and-a-half-year fight. Today, Sadie is considered cancer-free.

“It makes me feel like I’m strong when I look at this painting,” she says, of the self-portrait.

She knows her purpose – her passion – is far from over.

“Usually whenever people are done with chemo, they’re just done with cancer. They don’t want to talk about it anymore. They don’t want to do anything with it. but that’s not what I wanted to do. I wanted to take my treatment and turn it into something that would help other kids,” Sadie says.

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