(CBS) — A South Bend man is getting the new kidney he needs, thanks an unusual idea from his family, and the generosity of a stranger.

WBBM Newsradio’s Mike Krauser reports a huge billboard on a busy street in South Bend, Ind., showed the photo of a baby girl and asked passersby to “Please Donate the Kidney that will save my Grandpa’s life.”

The family of Jerry Graf, the baby’s grandfather, was hoping a stranger would donate a kidney.

“We were getting ready to go on dialysis. I’m to the point that I can’t go any longer,” he said.

It was a pretty big favor to ask of strangers, but it worked. Amy Pitrowki called the number on the billboard, got tested, and turned out to be a match.

“He’ll get to see his granddaughter grow up. You know, we can’t guarantee how long it’s going to be. Better outcome than what he has right now,” Pitrowski told WSBT-TV in South Bend.

Graf said Pitrowski is probably the most giving person he’s ever met.

“I think we’re going to be joined at the hips; our kidney,” he said.

His wife, Diane Graf, said they can’t put into words how thankful they are.

“Thank you buy no means covers the way we feel about her,” she said.

The transplant surgery is scheduled for next week.

The Grafs said more than 100 people responded to the billboard, but many of them don’t match. Those who don’t will be put on a list of donors, and might be matched with other patients who need a kidney.