FDNY firefighter John McNamara's wife, Jennifer, is a quick study.
The couple were set up on a date through a mutual friend on Sept. 9, 2000. He was a Bay Ridge, Brooklyn, firefighter.
She was a Brooklyn Heights lawyer.
"It took me about an hour to figure out I was going to marry him," Jennifer said to ABC News. "I think it took him a few more days."
"When I met him, he had these huge arms," she said. "He used to work out all the time. He never smoked, never did anything in excess. He was always in great health. He had to be, given his job."
In May 2001 they were married.
When the planes hit the World Trade Center towers, Jennifer was working at 40 Rector St. as a managing lawyer for the New York City Commission on Human Rights.
The landing gear of one of the planes crashed in front of her building.
John was called in for rescue, and worked all day and through most of the night.
He would spend about 500 hours in the smoldering mound of twisted metal dust that first responders came to refer to as "the Pile."
"The first few days we had paper masks," John said. "They handed out paper masks, and a guy gave me two of them and said, 'Double up. It'll be better for you if you double up on them.'"
John said it was a secondary concern because "you didn't worry about that at the time [because] you were worried about finding 343 missing firemen."
"Or 2,000-plus civilians."
Meanwhile, Jennifer was trapped in a restaurant called Moran's when the towers collapsed.
Both came home that first day drenched in dust.
"Even given everything that's happened to us," Jennifer said, turning to her husband, "he would do this all over again -- no question. That's the kind of guy John is."
"He's a great, strong, brave guy," Jennifer said. "But this has been really hard on him."
Flash forward five years to May 2006.
John, 41, is eating chicken salad at his firehouse. He can't keep it down.
"I was in agony," he said. "I was getting terrible stomach pains."
He went to a doctor and was told that his colon was 90 percent blocked by a tumor.
The tumor, by the time doctors caught it, had spread to his stomach and liver.
"John called me at work and said the doctor wanted to see us both immediately," Jennifer said.
"I remember thinking to myself, 'Oh God, this is not going to be good.' … I tried so hard to keep it together, but when we got there and they told me cancer I just completely lost it," John said. "We went home that night and cried. That first night was really, really rough."
The cancer was a mighty blow, both of them said, all the more so because at the time of the diagnosis, in June, Jennifer was three months pregnant.
Now she's six months pregnant.
"In many ways [the cancer] has brought us closer together," Jennifer said. "All the things that used to be important aren't anymore. Even the pregnancy takes a backseat to this, this true life-and-death situation."
John is among dozens of firefighters who have said to ABC News that they have grown bitterly angry as they've watched one "brother" after another be taken off active duty by FDNY doctors who tell them their lungs are so damaged that fighting another fire could kill them.