▶ Watch Video: Taylor Swift surprises fan who helped hundreds find bone marrow donors

As the lyrics to Taylor Swift’s hit song “Bad Blood” go: “‘Cause baby, now we got bad blood. You know it used to be mad love.” It’s an anthem about falling out of friendship, but to 14-year-old Hallie Barnard, who was born with a rare blood disorder, the song holds a much deeper meaning.

“Because I felt like it really applied to me. Because I felt like, ‘Oh my gosh, I’m like Taylor Swift. You know, I got bad blood,'” Barnard told CBS News during an interview in her backyard in Dallas.

At just 15 months old, Barnard was diagnosed with Diamon Blackfin Anemia, or DBA, and she spent most of her life in and out of the hospital. The Swiftie says she relied on the singer to bring her joy. When asked to choose a favorite song, it was difficult for the teen, who is in her freshman year of high school. 

The only way to survive DBA is with a bone marrow transplant and Barnard was desperate for one. But she knew thousands of other patients are, too. 

Hallie Barnard received a rotationplasty surgery to cut the cancer out of her leg at MD Anderson in Houston. 

Hallie Barnard

So, a few years ago, she decided to do something about it, creating her own foundation: Hallie’s Heroes. “It started selfishly as just trying to save my life, but then we realized there’s so many other children out there that needed a bone marrow transplant,” she said. “So, so far we’ve swabbed over 8,000 people and we found over 300 matches.”

After a 9-year wait, Barnard got her own match – through her own foundation. But more obstacles stood between her and normal life as a kid. The blood disorder led to a cancer diagnosis: osteosarcoma. She received surgery to cut the cancer out of her leg at MD Anderson in Houston. 

The recovery was grueling, but Hallie said she stayed hopeful.

“My survival instinct just kicked in. I was trying to do anything that I could to survive. So, of course, it was scary but in my mind, I was just thinking that I wanted to be at my siblings’ future weddings. I wanted to and play games and run again,” she said.

Hallie Barnard says her survival instinct – and Taylor Swift – helped her through a cancer battle and rotationplasty. 

CBS News

Her survival instinct – combined with Taylor Swift – helped her through her rotationplasty, where doctors cut her cancer out, and reattached her foot and ankle to her upper leg to work as a knee. 

“To escape it all, I would just kind of daydream. And sometimes I’d listen to her music and I’d daydream about [Swift] and meeting her and seeing her in person. And I guess, I dreamt about it, but I never thought that it’d be possible.”

Little did she know that one day her dream would become a reality. When a man named Ilan Saadia – whose mother was also treated for cancer at MD Anderson – heard about Hallie’s Heroes, he was inspired to help the selfless little girl who turned her own health battle into a way to help others. 

Saadia had two extra tickets to Taylor Swift’s concert in Houston— so he and his daughter Gabriella decided to give Hallie the surprise of a lifetime. 

Hallie Barnard attended Taylor Swift’s Houston concert, sitting in the front row with clever signs, thanks to Ilan Saadia, who was inspired to donate his extra tickets to her.

Hallie Barnard

Tickets to the “Eras” tour were notoriously hard to acquire, and when Gabriella offered them to Barnard on a Zoom call, she was shocked and enthusiastically accepted. Barnard and her mom met the Saadias in Houston last month and attended the concert with Gabriella and her friend – in the front row. 

It was the perfect way to celebrate recent news: Hallie beat cancer. She no longer has “bad blood” — and thanks to her foundation, hundreds of others can say the same.