A high school writing assignment began with a thank you letter, and ended with a tearful reunion between a teen and the surgeon who saved her life.

15 years ago, Ashli Taylor was born with a failing liver and needed a transplant to survive. She never met the surgeon who performed the operation, but she says the stories her parents told her about the experience had taught her to be grateful for everything she has.

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So when her creative writing class was told to write about anything, she penned a page-and-a-half long thank you letter to Dr. Robert Goldstein for saving her life as a child.

"You probably have no idea who I am, but you had a great impact in my life," Taylor wrote. "I know you've had a lot of patients over the years and they appreciate your work. But my parents' lives would be totally different if it weren't for you."

Dr. Goldstein was so moved, he drove two hours to surprise Ashli in front of her classmates in Temple, Texas.

"It had been 14 years and out of the blue you get a letter like this and I can't tell you what this means," the doctor told the Temple Daily Telegram. "The words moved everybody in the office."

After surprising her–flowers in his hand–he reached to embrace her and the two weren't the only ones to wipe away tears in the classroom.

"I got my letter," Dr. Goldstein told the class, pulling the folded-up note from the pocket of his scrubs. "I'm going to keep it."

With that, the class learned a lesson in just how powerful their words can be.

(WATCH the video from WFAA News below) — Photo: WFAA video