NEED TO KNOWPat Tillman was a safety for the Arizona Cardinals from 1998 to 2002

In 2002, Tillman decided to walk away from his NFL career to serve in the U.S. Army

More than two decades after Tillman was killed during his service, his loved ones honor him through charity, celebrating the causes he cared for

Those closest to late NFL star Pat Tillman continue to honor the things that mattered to him, more than two decades after his death.

Pat's Run is the Pat Tillman Foundation's signature annual fundraiser. The organization was set up to identify "remarkable military service members, veterans and spouses, empowering them with academic scholarships, lifelong leadership development opportunities and a diverse, global community of high-performing mentors and peers."

Tillman was drafted by the Arizona Cardinals in 1998 and served as a safety for the team through 2002. Moved by the events of Sept. 11, 2001, the NFL player turned down a $3.6 million contract to stay with the team, choosing to enlist in the U.S. Army instead.

It was during his time serving in Afghanistan in 2004 that Tillman was killed at the age of 27. His death was later determined to have resulted from friendly fire during an ambush on his platoon.

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We remember Pat Tillman today and every day, honoring the life he lived and the legacy he left behind.His sacrifice will never be forgotten. pic.twitter.com/gL8c7SCWBr

Co-founder Perry Edinger joined The Mike Broomhead Show, where he explained how they're still honoring Tillman and his legacy, over two decades after his death.

Recalling the first year the run was held, Edinger said, "There were probably 20 of us putting the run on. We didn't know what we were doing. We were doing everything we can."

"A couple of days before the run, I get a call from this lady, and she goes, 'We want to show up. Is there something we can do? The elementary school is going to show up and we'd like to see if you can help us in any way.' "

The caller then tells him that Tillman "came and read to our class every week on Monday, when they had the day off," a complete surprise to Edinger. "This was a friend of mine and everybody I talked to, nobody knew about it."

The call was from Gina Bertocchi, whose class Tillman would visit. "Pat would come in when he was on the Cardinals, and there were many times the kids would say things that would catch him off guard,” Bertocchi told Cronkite News.

“One year, a student asked him how many interceptions he had. He said, ‘Well, none,' but [he promised that after] the next one, he would bring the football to the class. That next week, he got an interception, came back signing it and giving it to the kids."

Edinger said of the connection, "To this day, we still find a way to do something special for that group."