(WBIR- KARNS) Beth Harris is the mother of five children, so it's safe to say she's selfless. But she made a decision to help a complete stranger long before she had kids.

"It was a great honor, responsibility, and privilege," Harris said.

Twenty years ago, she decided she wanted to make a difference. She spotted an organization on her college campus looking for bone marrow or stem cell donors.

The registry, Be the Match, told her it was a long shot. The statistics show about one out of 540 get called to to donate. But every year when her newsletter came, she would think about it.

"It was 18 or 19 years went by. By that point, I thought, if I've never heard from them I'm never going to," she said.

Then last summer, she got a letter saying her stem cells could be the last hope for a woman across the world.

"She's 50 years old. She had acute lymphoblastic leukemia, which is a long name that means she had a blood cancer that they could not cure any other way. This was her last chance," Beth said.

Out of 20 million potential donors registered with Be the Match worldwide, Beth was the only person compatible.

"So I felt like I had been called very specifically. This woman who I don't know and she doesn't know me across the world needed me specifically," Harris said.

After a couple of months of testing, Be the Match flew Beth to a Washington D.C. hospital for the procedure. The process of donating bone marrow is much more advanced than when Beth signed up. She said the process was painless and requires four hours hooked up to a device that cycles through your stem cells.

She took her teenage son, Josh, with her for support.

"It takes a special type of person to go do something unbelievable like this. It takes a certain amount of courage," Josh said.

A year later, sometimes it still doesn't feel real. The regular health updates she gets from the organization help her feel connected to the recipient. The latest update was a good report.

"I wake up some mornings and think, what a science fiction miracle, really. What a great time to be alive," said Harris.

The two have not met, but Beth says she prays for her and hopes to meet her someday.