Coutlress has a conversion disorder that has affected her leg function. She was diagnosed after a surgery last summer, reports say.
In the video, Garcia is visibly amazed by his date's first steps and lets out a scream before he bursts through the front door. He runs towards her, enveloping her in a huge hug. "Oh my God!" he says, "How did you do that?"
"At first he didn't respond right away, so I was like, 'OK, when is he going to realize I'm walking?'" Coultress told CBS4. "And then he backed up and made the 'oh!' and then I was like, 'there it is!' I felt so accomplished and joyful."
The two high schoolers laugh through tears of joy.
The moment was captured before prom even started, but it was already a night they'll remember forever.
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