It's going to be extremely expensive, said Harne's mother, Carol Keckler of Worleytown, Pa., who estimates she'll be saddled with at least $150,000 in medical bills and expenses not covered by private insurance.
That's why she turned to COTA, or Children's Organ Transplant Association, for help, Keckler said.
The Bloomington, Ind.-based charity helps families of transplant patients cover the high costs through local fund-raising campaigns.
The local campaign for Harne will kick off Tuesday with an organizational meeting at 8 p.m. in the South Hagerstown High School cafeteria.
Family friend Carol Staebler is heading up the effort, which she expects will run about six months with the goal of raising $150,000.
Meanwhile, COTA has vouched to cover the $50,000 needed to guarantee Harne's spot on the transplant waiting list at Johns Hopkins Hospital in Baltimore.
Harne is 11th down on the list in the small female category, her mother said.
That's a fairly good category, Keckler said, because the lungs could come from either a large adolescent or small adult.
Still, there's no telling when Harne will get the transplant, said Keckler, who blames the lack of organ donors for her daughter's dilemma.
"We're always in a state of anxiety ... waiting, waiting," she said. "If everybody signed their donor cards, there wouldn't be any reason for anybody dying because they need a transplant."
Keckler has already lost a son to cystic fibrosis, a genetic birth defect that affects the respiratory and digestive systems.
Harne's older brother, Jimmy, died on New Year's Eve in 1987 at the age of 14, Keckler said.
Like Harne, he had battled the disease - which coats the lungs with a thick, slimy mucus - since birth, she said.
He wasn't a candidate for transplant because he had developed an enlarged heart, Keckler said.
Harne - baptized at 8 weeks old because doctors feared she would soon die - has been able to lead a "fairly normal" life thanks to aggressive treatment through Johns Hopkins Hospital, her mother said.
Her condition deteriorated over time, however.
When she was younger, Harne required about four hospitalizations a year.
Now she's averaging three to four "good weeks" between week-long hospital stays and follow-up treatment at home, Keckler said.
Harne has to be hooked up to oxygen in order to breathe now.
That forced her to leave her secretarial job at First Data Merchant Services in February, Harne said.
They told her she could come back after she recovers from her transplant, she said.
Harne said she used to be scared she was going to die but now is confident the transplant will work and is anxious to get it over with.
While she'll still have to take special medication in order to digest her food, Harne will be able to breathe normally once she gets her new set of lungs, Keckler said.
Harne said she has already made plans to party and go to the beach when she's feeling better.
Meanwhile, Staebler is hoping to get the community to support the fund-raising campaign so Keckler - already near bankruptcy because of her daughter's illness - has one less thing to worry about.
An account for Harne has been set up at Home Federal Savings Bank, Staebler said.
The account contains $2,200 raised through a fund-raiser put on by students at South Hagerstown High School and some individual donations, she said.
All donations are 100 percent deductible and will go to reimburse Harne's medical bills and expenses related to the transplant, Staebler said.
Plans for raising the rest of the money include a dinner dance at the Greenbrier Inn on June 28, a ham sandwich sale and collection containers in area businesses, she said.
At least 14 volunteers are needed to help with the campaign, she said.
For information on the campaign, call Staebler at 301-733-0390.