It was one of those days for Jamie-Lynne Knighten. She stood at a market with a crying baby in her arms, a declined credit card, and no way to pay for the $200.00 in groceries in her cart. Add to that a growing line of impatient shoppers behind her.

Then Matthew Jackson stepped in.

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Knighten didn’t know Jackson, but he offered to pay her tab. Struggling to use her phone to call her bank, she at first declined.

Moments later with the line still growing, she accepted the kindness of this stranger. "It just felt like this huge hug, this great big bear hug," she told The San Diego Union-Times.

When she offered to pay him back Jackson told her he’d rather she promise to do the same for someone else sometime.

She agreed but collected Jackson’s name and number. A few days later, she was moved to call Jackson and say thank you one last time.

That’s when she heard the devastating news. When she asked Jackson’s boss if it was OK to bring him a thank you, the gym manager began to cry. Jackson had been killed when his car hit a tree near the same shopping complex where he came to Knighten’s aid. It was less than a day after his selfless act.

Jamie-Lynne needed a way to tell the world about Matthew. She chose Facebook where she wrote, "I thought for sure I would get the chance to see him again, give him a hug and thank him at least once more in person. Now I won't get that chance, but more importantly no one else will get the chance to meet him. And that breaks my heart."

Her post didn’t fall on deaf ears.

"It was incredible," she told the paper. "People saying they were going to pay it forward in Scotland, in Wisconsin, in Australia. Overwhelming. It was overwhelming."

Matthew’s mother said her son was always a compassionate child. Knighten vows to keep that memory alive.

“There has got to be some good to come of this,” she explained. “He would be happy to know that other people are learning from his example.”

It seems it’s already happening.

Matthew’s sister is married to a youth pastor from Gilbert, Arizona. On their way to the memorial service, they stopped to eat near Yuma. As they and their four kids finished and went to pay for their meal, they found it had already been done.

A random stranger paid for their dinner.

More here.