"You have to make tomorrow a better day," say Lee Ielpi, whose fire fighter son was murdered on Sept. 11. "I can't bring my son back, but we can do it better for the children of the world." — Photo by EPA/Justin Lane/Newscom

"I was one of the lucky dads; my son's entire body was recovered," says retired New York firefighter Lee Ielpi, 67, sitting in his Manhattan office overlooking the construction at Ground Zero.

Ielpi, a Long Island, N.Y., native and Vietnam veteran, is president of the September 11th Families' Association and co-founder of the association's Tribute WTC Visitor Center. The organization has trained 470 Ground Zero guides, each of whom survived the Sept. 11, 2001, terrorist attacks, lost a loved one or was a rescue or recovery worker. They lead guided walks and share their stories with visitors. So far 2.3 million people from 130 countries have visited the site.

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The five-year-old Tribute Center, an elaborate exhibit directly across from the former south tower of the World Trade Center, houses photos, artifacts and videos that tell the stories of 9/11 victims and survivors. A film portrays the efforts of the thousands who came from near and far to help. Heartfelt notes are left by visitors.

A day to remember

Like most people in America, Ielpi remembers well the day the twin towers fell. "I was already retired, sitting in my kitchen with my wife when the phone rang. It was my son Jonathan, saying, 'Dad, turn on the TV.' " Jonathan was 29, married and the father of two sons. He was also a fire fighter, like his dad.

"He saw on television what everyone else did but sensed it wasn't just about a small plane," Ielpi says. Jonathan immediately decided to go down to the World Trade Center. "I told him to be careful," Ielpi recalls. "It was the last time I ever heard the voice of my son."

A younger son, Brendan, also a fire fighter, also realized that the plane crashing into the towers was a terrorist attack. He and his father drove into the city together. Ielpi dropped Brendan at his firehouse and continued on to the World Trade Center.

"I arrived half an hour after the north tower had collapsed," Ielpi says. "My mission was to find my son, but I wound up staying nine months. It was chaos, like a war zone. The 16-acre footprint of both towers had turned into more than 20 feet of rubble." He says the air was a cloud of substance, filled with debris, making it difficult to breathe.

"I came across the first fatality, a fire fighter lying on the ground," Ielpi says. Someone had put a fire fighter's protective coat over the man's face. "If you could find someone alive it was a blessing for that family. If you found someone dead, it was still a blessing. I never found anyone alive.

"It was like, you'd say, 'Did you see my son?' 'No. Did you see my dad?' Four months ago someone answered the telephone — almost 10 years later — to be told a body part had been identified. They don't tell you what they found; you don't want to ask. Some families are notified 10, 12 times. This will probably go on and on … even my children's children won't hear the end of this."

Next: Keeping the faith. >>