"I was like, 'I don't even know you!'" Mother buying diapers shocked when stranger pays it forward

SOUTH DAKOTA (WITI) -- "I couldn't believe it. I was just so surprised! I was like, 'I don't even know you!'" Katie Kanefke said, after a trip to Walmart this past weekend.

The South Dakota mom was at the store buying diapers for her infant son, when she asked Walmart workers if they could price match all four boxes of diapers she planned to buy.

When workers said no -- that they could only price match one box, Kanefke planned to put three of the boxes back on the shelf.

That is when fellow shopper, and total stranger Carol Flynn stepped in -- according to WTVR.

"It looks to me like you had four boxes of Pampers and you're only buying one," Flynn recalls saying to Kanefke.

"So I said 'do you have children?' And she said 'Yes, I have a little boy who is four months -- and he uses a lot of diapers.' I said 'I think you need the other three boxes then,'" Flynn said.

Flynn "paid it forward" quite literally -- purchasing the extra diapers for Kanefke's son.

A third Walmart shopper recorded the act of kindness on video.

“I never expected to have it videotaped. It went viral, which I’m told meant you could go on Facebook and find the article, which I did. It was very surprising to me," Flynn said.

Flynn says she told Kanefke paying it forward was a "neat thing to do" -- and encouraged her to pay it forward to someone else.

CLICK HERE for more on this story via WTVR.