KANSAS CITY, Mo. — Three people in downtown Kansas City on Tuesday had their day brightened just a little bit because of a non-profit born out of a tragedy more than two decades earlier.

For the first 11 days of September every year, Pay It Forward 9/11 challenges people all over the world to do random nice things for strangers with only one string attached: That those people do something nice for someone else as well.

It’s meant to honor 9/11 first responders and the population of Gander, Newfoundland who took in about 7,000 travelers on more than two dozen planes that were grounded after the terror attacks on the east coast.

“[Gander] took [travelers] into their homes, they fed them, they gave them places to stay and just made sure while they were there they were as comfortable as they could possibly be,” said Pay It Forward 9/11 Board Member Ben Walker.

Walker himself was stranded in Canada and had to drive all the way home to Texas. His friend Kevin Tuerff was one of the travelers stranded in Gander and became part of the story memorialized in the hit Broadway play, Come From Away.

In the metro, Walker and his friend Ricardo Reyes filled up a stranger’s gas tank and handed out gift cards for coffee and groceries.

“This is like the third time I’ve done this, and it just feels amazing,” said Reyes.

“There is a legacy out of 9/11 that’s not just maybe the worst day in America’s history but we’re making our society a little bit better as a result of their sacrifice,” said Walker. “It starts a ripple effect, and it builds and builds on itself and it just makes Kansas City a better place to live.”

Pay It Forward 9/11 tracks where random acts of kindness happen around the world. You can find that here.