On a late summer day in 1994, Queens rescue firefighter Terrence Farrell had lunch with a 6-year-old girl in a frilly white dress on the 87th floor of the World Trade Center, to celebrate the life he had given her.

Bone marrow donated by Farrell had been used to cure the blood cancer that was killing Chantyl Peterson. She had flown in with her family from Nevada to give him flowers and kisses. She rode his fire truck and enjoyed a picnic with the Dix Hills Fire Department, where Farrell, a Huntington resident, also serves as an assistant chief. She called him "my Mr. Nice Man." He called her his "daughter by proxy," and got a little choked up.

So this week, when Chantyl's mother saw the Twin Towers collapse on CNN and found out Terry Farrell was missing, "I just wanted to get in my van and go to New York and start looking for him," Sheri Peterson said from their home in Henderson, near Las Vegas. When Chantyl's father, Robert, a goldmine foreman, pointed out that the drive would take seven days and that they wouldn't be allowed anywhere near the scene, "I said, 'You know, that man moved mountains for us,'" Sheri Peterson said. "Why can't we be there to move some debris for him?" Once too weak from radiation treatments to do more than lie in front of the TV, Chantyl is now a horse-crazy seventh-grader enjoying "full-blown puberty," her mom said. Pictures of Farrell are tucked among the school award certificates on the A student's bedroom wall. Chantyl returned to New York two years ago for a surprise reunion with Farrell, who has two kids of his own, and a fireboat ride in New York Harbor. The families planned to get together every five years.

This week, Sheri Peterson said she has called Farrell's wife, Nora, every day to offer encouragement. The telephone voice of the firefighter's wife has gone from upbeat to shaky as the days passed. On Friday, Nora Farrell said family members were coming and they were all going to church. "She said we should go and pray too, not just for Terry, but for the nation, because she was scared for us, for the nation, for the United States," Sheri Peterson said.