(CNN) -- Sarah Murnaghan, the 10-year-old girl whose quest for a lung transplant prompted a change in national policy, is up and walking.
"Sarah walked 10 feet with her walker for the first time, actually made it out of the room!!!!!" her mother, Janet Murnaghan, posted Tuesday on Facebook.
The girl was helped by a physical therapist.
The family's hope is that Sarah will soon be able to walk on her own -- something Janet Murnaghan has said she sees as the last major obstacle to leaving a Philadelphia hospital.
"The physical (component) is what's holding us back, more than her lungs, more than anything else. Her lungs look fantastic on the X-rays right now," Sarah's mom told CNN last week.
Sarah, who turns 11 on Wednesday, was born with cystic fibrosis. She was on the transplant list for children's lungs for 18 months.
Sarah wasn't able to qualify for adult lungs because she was too young; the agency that oversees transplants, the Organ Procurement and Transplant Network, had a policy that children only 12 or older could be prioritized for adult organs.
The family petitioned Health and Human Services Secretary Kathleen Sebelius to change the rules so Sarah could qualify for adult lungs. They argued the rule was unfair, and several lawmakers asked Sebelius to act.
The organ network approved a change to their policy to allow lung transplant programs to request additional priority for younger transplant candidates. The change is effective for a year, when it must be approved by the board of directors.
Sarah underwent two lung transplants days apart.
The original transplant on June 12 at Children's Hospital of Philadelphia reportedly went smoothly but that evening "... an emergency code blue was announced. Sarah's vital signs had begun descending rapidly as her new lungs started to fail," her family said in a statement.
The girl underwent surgery immediately and was transitioned to a bypass machine that took over the function of her heart and lungs, the statement continued.
She remained on the bypass machine -- "her doctors prepared us for the probability that Sarah would die, either before a second surgery could take place or on the operating table," her family said -- until June 15, when new lungs became available and a second transplant took place.
Although the donated lungs were infected with pneumonia, "Each day since (the second transplant), her lungs have improved on X-ray and have continued to work better and better," the statement said.
CNN's Chris Welch and Melissa Gray contributed to this report.