On the Friday before Christmas, Ruby Modlin was grocery shopping at Walmart with her family.

The Altoona, Iowa woman noticed that a man was following her around the store. Being a glass-half-filled type of gal Modlin figured it must be somebody who recognized her -- maybe from high school.

"I kept noticing this man, and I'd smile at him," Modlin said.

It was when her family got to the checkout line that the unknown man made his good intentions known by jumping in front of them and swiping his card on their $211 bill.

“He said, ‘That’s my daughter and wife over there. We just wanted to come out and do something nice for somebody, and we picked you guys,’” Modlin explained.

What the man couldn't know -- and what made his holiday gesture all the more powerful -- was that Modlin had suffered liver failure six months ago and had been in and out of hospitals ever since as she awaits a transplant. The expense of her treatment had been weighing on the family as they shopped.

"They're just sent from heaven. There's no amount of words that can thank people like that," Modlin's husband Ray said of the Santa whose identity still remains secret.

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