In September 2005, Stapleton began a 14-month cycle of dialysis during which he spent four hours a day, three days a week, receiving dialysis treatment that he scheduled around his full-time job.

"I was supposed to be going out and having fun with my friends," Stapleton said comparing his life to that of other 21-year-olds. "But on Monday, Wednesday and Friday, I was hooked up to a machine while everyone else was going out."

In January, 2006, Stapleton went to University of Maryland Medical Center with his mother, younger sister, his friend Tara, now his wife of two years, and three other friends to see if any were suitable for a transplant.

"On Valentine's Day, each one of us slowly but surely started getting phone calls," said his mother, a Severn resident. "All six of us found out that we were a match."

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But that joy quickly turned to despair as all six were disqualified for various reasons.

"When people started getting eliminated one by one, it was an emotional roller coaster," Stapleton said.

He noted the reasons for their disqualification provided them with important news about their health they wouldn't have received otherwise.

Eventually doctors re-tested Thomas. On Dec. 27, 2006, a date both Stapleton and his mother rattle off without thinking, she donated a kidney to her son.

Though his body initially rejected the organ — typical in transplants — and his required medications have taken some getting used to, Stapleton said his recovery has gone well.

He's ready to rappel down a building and by doing so raise awareness about kidney disease.

The first two events put on by the Maryland chapter of the National Kidney Foundation drew 135 participants and raised $180,000, according to a release from the foundation

Stapleton's mother rappelled down the Legg Mason building in the Harbor East neighborhood of the city at the inaugural event.

"It was just something that I felt I needed to do," Thomas said.

The most difficult part of the event was just getting started.

"You go over the edge of the building and you got your toes on the edge," Thomas said. "You're putting all your trust in the ropes."

Part of her motivation to rappel the building two years ago was knowing her son was at the bottom of the building, waiting for her.

This year, mother and son will rappel the building side-by-side.

"She was able to donate to me. She was able to change my quality of life," Stapleton said. "It's definitely going to be rewarding."

Any emotional exchanges will likely have to wait until after both have made it to the bottom, however.

"I'm pretty sure the only time I'm going to look over at her is right before, and once down," Stapleton said. "I'm not sure there's going to be much conversation between us on the way down."