After hearing he needed a transplant, the relative from Florida reached out to him on social media.
"My wife's cousin's daughter, who came forward out of nowhere, sent me an email that says, 'Hey, Uncle Mike, can I be your donor? Can I try?'" Hermogeno told ABC station KABC in Los Angeles.
Jackie Tunaya was a bridesmaid at Hermogeno's wedding 17 years ago and her mother is the cousin of Hermogeno's wife. Tunaya said she was inspired by both her uncle and her mother to help.
"Turning to my husband, I said, 'I want to help this person and he's family so I want to help,'" she told KABC.
Tunaya’s mother had donated a kidney 17 years ago, helping to save someone else. Her mother, Susan Romero, said she is impressed with her daughter's decision.
"Who knew that 17 years later she would do the same thing? I'm so proud of her," Romero told KABC.
Hermogeno’s surgery is scheduled for today at UCLA.