Hanna Alzein who, her parents say in a lawsuit filed this week, received improper care at the Alberta Children's Hospital in Calgary, sits with her family in the living room of their home. (CBC)

A $1 million lawsuit has been filed against Alberta Children's Hospital by a Calgary family.

Papers filed in court this week claim a young girl suffered serious brain damage, blindness and other injuries as a result of improper care.

Awatef Alzien said her 11-year-old daughter, Hanna, who has Down syndrome, used to walk, swim and speak two different languages. That all changed, she said, after what the family thought would be a routine trip to the Alberta Children's Hospital in January 2008.

Hanna, who was eight at the time, was admitted to hospital to treat an excess mucus problem in her chest, according to the lawsuit. The family has said she was given too much Ventolin — a drug typically used to treat asthma — and that accelerated her heart rate and caused a lung to collapse.

"She start her lips blue. She can't breath. It's her lungs collapse. Right away to the ICU," Awatef, recalling the incident, told CBC News.

'I can't leave her. I don't trust anybody.'— Awatef Alzien

The lawsuit also claims Hanna was given a blood transfusion meant for another patient of the same first name who had leukemia, and that she was prescribed too much of a medication designed to remove excess fluid from the body, thereby causing dehydration.

Following a series of what the family calls treatment errors and equipment issues, the girl went into cardiac arrest and suffered oxygen deficiency for an extended period of time.

"Say bye-bye to your daughter," Awatef said. "She's gone, and they start to pull all the tube."

Hanna survived but suffered liver and kidney damage, blindness and brain damage. Confined to a wheelchair, her parents now provide her with around-the-clock care.

"I am with her every day," said Awatef. "I can't leave her. I don't trust anybody."

Father blames himself

Hanna's father, Bchar Alzien, said from that point on, he hasn't liked Hanna seeing doctors.

"I don't like her to feel … crying. It means pain," he said. "I'm scared to go to doctors. I'm scared to go to hospital."

While the family blames the hospital and the medical staff who treated Hanna, her father said his own guilt keeps him awake at night.

"My fault, because my wife, she wanted to take her out of the hospital … I told her, 'No'," he said.

Bchar and Awatef Alzien put their daughter Hanna to bed. (CBC)The Alziens are seeking $950,000 in damages, plus the cost of their daughter's future care.

They hold on to the hope her condition might improve one day.

"I want Hanna back," Awatef said. "I want to try my best to have Hanna back."

None of the allegations have been proven in court.

A spokesperson with Alberta Health Services said the agency can't comment on the lawsuit at this time. A statement of defence hasn't yet been filed.