CHICAGO (CBS) He's being called a miracle.

Doctors first thought 14-year-old Mario Palomares wouldn't survive the night after a horrific crash. On Thursday, he left the hospital.

CBS 2's Vince Gerasole reports.

For Mario, each step he can take and each smile he can make is a miracle -- just ask his family.

"He's walking, he's talking," his brother, Jonathan Palomares, said. "My mom always prayed to God that he would be all right."

Mario, who moves gingerly through therapy now, wasn't expected to last the night when he was hit by a car coming home from school last May.

"When we first encountered him he was in a very critical state, on death's door, essentially," neurosurgeon Kevin Waldron said.

The pressure on his brain was 10 times that of a normal person, enough to shut it down immediately. Doctors at Hope Children's Hospital had to remove portions of his skull to save his life, but for months they were uncertain if Mario could ever bounce back.

"We didn't know how well he was going to be able to function -- what Mario was going to be able to do -- because he wasn't very responsive," says Dr. Douglas Koltun, director of pediatric rehabilitation.

Mario said it feels good to be able to move around. That he can have a conversation this simple is a credit to his doctors and therapists, but also to the love of his mother, Maria Guillen.

"She was here practically around the clock," Koltun said.

Credit also goes to his brother Jonathan, 16, who interpreted critical information from English to Spanish.

"There was good news and bad news -- but they always turned out to be good news," he says.

Koltun says the teen's progress has been surprising.

"He's not going to be exactly how things were, but how he's progressed already has truly astounded me," he says.

Mario can understand most of what's said to him, and his verbal responses continue to improve daily. Doctors say recovery from head injuries is slow, but it's quite possible Mario, with therapy, will be speaking and moving a lot closer to his old self in the months ahead.