NEW YORK (CBSNewYork) — The 15th annual Tunnel to Towers run and walk will be held on Sunday. It’s a tribute to firefighter Stephen Siller who was killed on 9/11.

For many participants, the event is a source of comfort and healing.

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As CBS2’s Dick Brennan reported, the charity has taken one of the darkest days in American history and turned it into a foundation that continues to give back to those who protect and serve our country.

Web Extra: Tunnel To Towers Run And Walk Guide

“We have firefighters from all over the U.S. and police from all over the U.S. that go through the tunnel and retrace my brother’s final historic footsteps that he took to get there on 9/11 where he gave up his life,” Tunnel to Towers Foundation, Chairman and CEO, Frank Siller said.

On September 11, Stephen was off duty, and on his way to meet his brothers to play golf when his scanner alerted him to the attacks on the World Trade Center. He turned around and grabbed his turnout gear instead of his golf clubs and raced to the burning towers. His truck was stopped at the Brooklyn Battery Tunnel, undaunted he strapped on 60 lbs of gear, and ran through the tunnel and into history.

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“That’s my brother. He was always looking to help people out. I’m sure he was thinking about his family as he was running to the towers, but his duty overcame everything,” brother, George Siller said.

“When the towers went down I turned to my mother-in-law and said I just lost my brother,” Frank added.

The foundation was formed in Stephen’s honor. They started the Building for America’s Bravest program, which designs and constructs homes for the most critically wounded soldiers. The uber high-tech homes allow heroes to be in their homes alone and regain control of their lives.

“We come together, and we know the sacrifice that was made by these men and women in uniform, and what better way to say thank you than building them a home,” Frank said.

The Tunnel to Towers special will air on CBS2 at 10:30 a.m. on Sunday. Face the Nation will run at 1 p.m.

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