Kropp was traveling for work last spring, when he got a life-altering phone call from his doctor.

"It was incredibly shocking. I just literally dropped all my stuff and sat on the floor, and just, you know, asked God ‘Why me?" Kropp said.

The 46-year-old's doctor told him his kidneys were failing, it was an emergency, and he had to get straight to the hospital.

"I jumped on a plane, and flew back home, and said, 'let’s tackle this," said Kropp.

Kropp went straight to the hospital, where he spent the next seven days.

"I went into the hospital at eight percent kidney function, and I left at four percent, so I was on a downhill slide," said Kropp.

Before that call in the airport, Kropp had no idea he was sick.

He had been having headaches, some swelling in his legs, and he was always tired.

But, he just thought that's what happens after you turn 40, and he was traveling every week, flying from coast to coast, for work.

"I didn't realize how bad I felt before," said Kropp.

Days after the phone call in the airport, Kropp started dialysis.

His wife told her friends what was happening, and they started looking for a donor.

"Through social media, good 'ol Facebook," said Kropp.

That's when mutual friend of the couple's reached out and volunteered for something few would. Veterinarian Dr. Chris Kelley wanted to give Kropp his kidney.

In November, they learned Kelley was a perfect match.

Less than a month later, both men were lying on separate operating tables, in Oklahoma City.

"Words can't describe what this gift is," said Kropp. "There's a lot of things I want to accomplish in my life, and I have that opportunity, thanks to Dr. Kelley. There’s gonna be some events in life that I wouldn’t have been able to see, without this gift, and now I will, (like) seeing my daughter get married, seeing my kids grow up."

Kropp says being a living organ donor shows incredible character.

He hopes by sharing his story, more people will consider saying "yes" to organ donation.

Kelley and Kropp are both back at work, and his prognosis remains good.