Sioux Falls, SD -

A video of a stranger buying diapers for a cash-strapped mother in a Sioux Falls store has become a big hit on Facebook.

The video, shot and posted by Jason Yoshino, has drawn more than 4,000 likes and hundreds of comments, and been shared more than 1,000 times.

Yoshino captured the moment Sunday night when Carol Flynn bought three packages of diapers for Katie Kanefke when the store clerk declined to match a competing store's lower price.

Flynn says she didn't shell out $120 for the diapers to receive attention. She says she just wanted to help out.

Kanefke says she was shocked by Flynn's generosity and grateful. She says it brought her to tears.

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