(CNN) When Becca Bundy's young daughter was having a seizure at home, volunteer firefighter Bill Cox was the first person to help. Two years later, the Minnesota woman was able to offer a lifesaving thank you, by giving him one of her kidneys.

Cox has volunteered with the Bearville Volunteer Fire Department in northern Minnesota for about six years and is trained as a first responder. He got the call to help Bundy's daughter in August 2016.

"I got there and helped settle people down until an ambulance could get there and take care of her," he told CNN.

The two met again in October 2018 when Bundy went to a benefit for a neighbor at the Viking Bar, where Cox has worked for 16 years.

Cox was tending bar, wearing a bright green T-shirt that said that "My Name is Bill. I'm in end stage KIDNEY FAILURE And in need of a KIDNEY."

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