Near the southern tip of Manhattan, each name of the 2,977 victims of 9/11 is inscribed in stone.

Americans have vowed to remember those who died during the terrorist attacks on Sept. 11, 2001. But so many more have been forgotten.

Rob Serra had just started with the New York City Fire Department when the Twin Towers fell down. He now has neuropathy, a condition that numbs his feet, and he uses a wheelchair. Serra was lucky enough to survive, but many first responders have died in the years since, suffering from health problems related to the attack.

“We might have stopped the recovery efforts on that day,” Serra told the New York Times, “but for a lot of us, it never stopped.”

Serra attended the opening of the Memorial Glade in New York City last month, as the city unveiled an addition to its 9/11 Memorial, honoring more than just the first 3,000 victims. An inscription dedicates it to "those whose actions in our time of need led to their injury, sickness and death."

The issue is not simply one of remembrance, though. Healthcare bills and illnesses still ravage many first responders' lives, and comedian Jon Stewart has become a vocal champion of 9/11’s forgotten victims.

A video of Stewart’s testimony before the House Judiciary Subcommittee on the Constitution went viral, as he argued that Congress must renew the September 11th Victim Compensation Fund, which will run out in December 2020.

“Certainly, 9/11 first responders shouldn’t have to decide whether to live or to have a place to live,” he said. “The idea that you can only give them five more years of the VCF because you’re not quite sure what’s going to happen five years from now? Well, I can tell you. I’m pretty sure what’s going to happen five years from now: More of these men and women are going to get sick, and they are going to die.”

The fund's administrator has said it may run out sooner than its 2020 expiration. A new bill, which has advanced out of committee and is expected to pass the House, would clear all necessary funding for victims until 2090.

Meanwhile, 9/11 first responders are still dealing with the aftermath of the attack. One of them is Luis Alvarez, an NYPD detective who testified with Stewart and was put in hospice care this week. During his testimony, though, he said he wouldn't have done his job any differently.

“I can tell you that I did not want to be anywhere else than ground zero when I was there,” he said. “We were part of showing the world that we would never back down from terrorism, and that we could all work together.”