ST. LOUIS - A Canadian couple transferred their terminally ill toddler son to a Catholic hospital in St. Louis after an Ontario court ruled that doctors could remove the breathing tube keeping the boy alive.

Thirteen-month-old Joseph Maraachli arrived at Cardinal Glennon Children's Hospital on Sunday after the hospital agreed to treat the boy.

Joseph's doctors at London Health Sciences Centre in Ontario, where he had been treated since October, determined that he was in a permanent vegetative state and that his condition was deteriorating, and they planned to take him off of assisted breathing.

Joseph's parents, who lost an 18-month-old child to the same disease eight years ago, challenged the hospital's finding in court but lost.

Moe Maraachli and Sana Nader contended that removing their son's breathing tube would cause him to suffocate and cause him undue suffering, and they sought to compel doctors to give Joseph a tracheotomy that would allow him to breathe through a tube inserted into his throat. They said the tracheotomy could extend his life up to six months -- as they say it did for their other child who died -- and would allow him to die at home.

After losing in the courts, Joseph's parents enlisted support for their cause using social media sites, but the hospital refused to reverse course. So they began reaching out to U.S. hospitals, and Cardinal Glennon agreed to care for their son.

Late Sunday, a plane carrying Joseph, his father, and the Rev. Frank Pavone of the New York City-based group Priests for Life flew to Cardinal Glennon. Priests for Life, which lobbies against abortion rights and euthanasia, paid for the chartered plane.

Moe Maraachli did not immediately return phone messages seeking comment Monday. But Pavone said the parents are simply trying to extend the life of their child and make sure he doesn't suffer.

"The parents are saying, 'Look, even if the diagnosis is fatal, let's give him the best care he can get,"' Pavone said. "They're saying, 'This is our child. We believe his life is worth extending."'

Pavone said the exact disease from which Joseph suffers has not been determined. The Ontario hospital, in a news release, called it a "progressively deteriorating neurological condition" and said the move to St. Louis was against the advice of its medical staff. Joseph breathes with help from a machine and receives nourishment through a feeding tube, the hospital said.

Cardinal Glennon spokeswoman Ashley Wiehle said doctors "are in the process of evaluating Joseph and forming a treatment plan. Like we do for all the children here at Cardinal Glennon, we want to provide the best care possible for him and do what's best for him."

Wiehle said it wasn't known how long Joseph would stay at Cardinal Glennon.

London Health Sciences Centre said the hospital's judgment was supported by various pediatric specialists in both countries along with Ontario's Consent and Capacity Board.

"LHSC continues to be proud to stand behind their judgments and the care given to Baby Joseph," hospital chief executive officer Bonnie Adamson said in the release. "The judgments were sound, both medically and ethically, and the care Baby Joseph received from our staff was second to none anywhere in the world."

Rebecca Dresser, a professor of law and medical ethics at Washington University in St. Louis, said U.S. courts generally side with families in such cases that want to continue treatment for loved ones even in seemingly hopeless medical cases.

Dresser said similar end-of-life cases will likely become more common.

"Because of the growing concerns about costs, we're going to see more of this," she said.