The BMW Dallas Marathon is just weeks away, and for one North Texas teen, crossing the finish line will mean far more than a personal record.

Seventeen-year-old Riley Morrison is preparing for her first marathon, something she once believed would never be possible. Less than two years ago, even walking could cause pain.

"If I walked for too long, it would start to ache on my right side, and my posture was so bad, I stood like this all the time," she said.

Morrison was diagnosed with scoliosis in seventh grade. Even with a back brace, the curves in her spine kept progressing.

"My back was shaped like an 'S', so I had my biggest curve at 60 degrees, and my other was 20 degrees," she said.

By last January, surgery at Scottish Rite for Children had become her only option.

"It was like a 4-5 hour surgery, two metal rods, 15 screws...I grew 2.5 inches, and my back is now perfectly straight," Morrison said. "The team there did a fantastic job, and I am so grateful for them."

Recovery meant months of relearning how to move. But as she healed, she began to see what her body was capable of. Inspired by her dad, a lifelong runner, she decided to try running herself.

"I slowly started to run a mile a day," she said.

She completed her first half-marathon in February and loved it. Now, less than two years after spinal surgery, she's training for the BMW Dallas Marathon.

"I am really excited to have this shared goal with my dad, and I am excited for him to watch me run this race..." she said.

When you see her logging miles before sunrise, it's clear how far she has come. Her goal is to finish in under four hours, but the real victory is proving something to herself.

"I am excited to prove to myself that I can accomplish my big goals and dreams," she said.