Sofia Sanchez's journey from heart failure to healthy, thankful 11-year-old

DOWNERS GROVE, Ill. (WLS) -- Sofia Sanchez is a little girl with a whole lot of gratitude and zest for life.

"I'm just so thankful for everything and I don't even know how to say it. It's just, I'm so thankful," she said.

The world first heard about Sofia in August when her "Kiki Challenge" video went viral and was viewed by millions.

What the world didn't see was the journey to get here.

It started back in January when Sofia, a healthy, active 10-year-old, suddenly had trouble breathing. She was initially diagnosed with asthma.

Still not feeling well in May, and now losing weight, Sofia was given more asthma medication.

By the last day of school in June, her heart was failing.

"We had a party after school. There was a big hill and I couldn't even run up the hill with my friends," Sofia said, saying that, at the time, she thought she was just tired.

"She couldn't sleep when she'd lay flat, she couldn't breath, so I would prop her up with pillows," said Sofia's mom, Natalie, said.

Natalie Sanchez rushed her daughter to the emergency room and insisted on more tests.

"I knew something was wrong," she said. "I wasn't gonna give up. She wasn't the same little girl."

"My mom begged and cried to them, 'Please do more tests to her, something is wrong,'" Sofia said. "They came back two hours later and said, 'You're right. You saved your daughter's life.'"

Sofia was quickly transferred to Lurie Children's Hospital and there she was diagnosed with cardiomyopathy. Her heart was pumping at 12 percent.

"They said she was the sickest patient in the hospital, if not Illinois," Natalie said.

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Seven weeks after being on the heart transplant list and just days after turning 11, another video of Sofia went viral - this time, showing her reaction to hearing that her other birthday wish, besides meeting Drake, was coming true: She was getting a heart.

The 9-hour surgery was a success. Sofia said she'll never forget the first time she took a deep breath without oxygen tubes in her nose.

"I haven't been able to breath in years this much!" she thought to herself.

Today Sofia is almost back to her normal routine, even throwing out the first pitch at a softball tournament raising money to help her with mounting medical bills.

Sofia shared a bracelet with ABC7 Chicago's Judy Hsu that said, "I heart organ donors. One saved my life."

The Sanchez family is forever linked to a family that they've never met.

"I just want to say thank you, and one day I hope to meet you," Sofia said.

"I just would want them to see how much she loves life and how much they did for her," Natalie Sanchez said. "I'm so, so thankful. So thankful. I couldn't live without my baby girl."

Fourteen Lurie Children's Hospital patients and 3,800 patients nationwide are still waiting for heart transplants.