Lung transplant recipient Sarah Murnaghan, seated at right, is surrounded by her family after her return Tuesday to her suburban Philadelphia home. Sarah spent six months in a hospital and underwent two transplant operations.

NEWTOWN SQUARE, Pa. — After six months in a hospital and two lung transplants, an 11-year-old suburban Philadelphia girl returned home to face challenges new and old.

Sarah Murnaghan will endure physical therapy, weekly hospital checkups and efforts to wean her from a machine that helps her breathe. She’ll also be starting fifth grade, even if it’s at home with visiting teachers.

“I think the disease cystic fibrosis makes fighters out of kids. She’s spent her whole life fighting,” Janet Murnaghan told reporters Tuesday outside her Newtown Square home, where her daughter returned to find bright balloons, excited neighbors, and a throng of reporters who had chronicled the family’s fight against national transplant rules.

The Murnaghans went to federal court to challenge rules that put children like Sarah at the end of the waiting list for adult lungs. Yet Sarah, critically ill at Children’s Hospital of Philadelphia, did not qualify for the adolescent list, which is for children 12 and up.

“We didn’t know if she would live, and the system was up against us,” Janet Murnaghan said.

A federal judge intervened, forcing the Organ Procurement and Transplantation Network — the private nonprofit group that manages U.S. organ allocation — to add Sarah to the adult list.

The case raised questions among some health specialists and medical ethicists about how organ donation rules are developed and under what circumstances they might be disregarded.

Anne Paschke, of the United Network for Organ Sharing, said the temporary option for other children to apply for adult lungs will be in effect until the end of June 2014.