A friendship that started at the check-out counter at a grocery store ended up in a Chicago hospital after a public school social worker decided to donate a kidney to his favorite cashier.

Myra de la Vega and Dan Coyne met after Dan chose to ring up his groceries in Myra's check-out line.

It was a routine that continued for three years until Dan learned 49-year-old Myra was sick and needed a kidney transplant. After discussing the matter with his family, Dan decided to help.

He later got tested and discovered he was a match.

"She just busted out crying with joy. Actually, her knees buckled, and I had to get her off the floor she was so happy," Dan said.

Now, after a successful life-saving surgery that may have extended her life by 25 to 30 years, Myra has dubbed Dan her "angel."

But the 52-year-old social worker insisted, "It's not about me, and it's not about Myra. It's really about doing the right thing."

"To see her in the chair this morning warmed my heart," he said. "Her skin color's back. She told me her energy is back. It's all looking good."

Myra's teen daughter said the touching gesture was straight out of a movie. But Dan said it was his faith that helped him make such a generous gift.

"Sometimes I think we have large God with a gentle voice that whispers," he said. "And I just felt it's the right thing to do would be to offer this."