A small act of kindness from a child made a world of difference for a man tasked with the grimmest of tasks during some of America's darkest days. 

Dave Triola, a Teamster from Local 445 in New York, spent the weeks following September 11, 2001 hauling debris from the wreckage that was once the World Trade Center buildings in his 34-foot dump trailer.

Two weeks into his run of heart-wrenching 12-hour shifts, Triola stopped at a respite center to get yet another pair of new gloves—his were getting dirty fast. He grabbed a pair of heavy-duty, gray and green ones. He shoved his hand into the left glove and was surprised to feel a small, folded-up piece of paper wedged inside. He unfolded it to find a short message written in pencil.

"Dear Fireman," the letter began in a child's shaky scrawl. "These gloves are to help you when you search for bodies. Thank you for helping other people. From Emily Ernspiker, Age 7. 1545 McKay Ave Louisville, KY 40213"

And that's when he broke down, Triola told the Courier Journal.

"My friend Mike said, ‘What is it?'" he recalled. "I couldn't even tell him. I just handed it to him. He had the same reaction."

He lasted about another month in that job. "I couldn't handle it," he explained. "It was very hard to get my head around how people could do this to each other. The destruction, the sadness of it."

He's since moved on to other jobs, and for nearly two decades he's held onto the letter that brought him to tears all those years ago. He keeps it, folded back into its original square, inside the pair of gloves he never wore, in his bottom dresser drawer. He told the Journal that he often wondered about Emily in Louisville—whether or not she got the letter her wrote back. Thinking about it now, it still brings him to tears.

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Every year he posts a photo of the letter on Facebook, asking his friends "please don't forget this."

Recently, thanks to a Courier Journal reporter, Triola and Emily met for the first time. It was her 23rd birthday, and she brought her two young daughters with her. She showed Triola of photo of herself when she was seven, and again he cried.

Emily revealed that the gloves were part of a deal Krispy Kreme was running at the time: donate gloves for workers at Ground Zero and get a free doughnut. The letter, she noted, was her idea.

"What led me to call the paper was the fact that things are split down the middle as far as our country goes," Triola said. "I thought sharing this story would kind of make people remember how everyone was getting along right after this happened."

Sitting in the summer heat, they agreed: small things add up to big things.