Alberta mental health worker Valerie Wolski never would have agreed to care for the mentally disabled man later accused of killing her if she had known how dangerous he was, her family said in an exclusive interview with CBC News.

Terrence Saddleback, 26, was charged with manslaughter in the Feb. 12, 2011, strangulation of Wolski, 41, a worker with the Canadian Mental Health Association in Camrose, Alta. In March, he was found unfit to stand trial.

"She said he gave her the heebie-jeebies," Wolski's mother Liz McGregor said this week. "But that was her job and she needed the job. But I think if she'd have known the dangers, she might have not been quite so quick to go in there."

Mother Liz McGregor, sister Theresa McGregor and brother Cliff McGregor all have questions about Valerie Wolski's death. (CBC)

Documents obtained by CBC News show that Saddleback was considered to be a threat to anyone who cared for him. A risk assessment warned he had a history of attacking female workers and would likely do so again.

A preliminary provincial investigation found that the Red Deer office of Persons with Developmental Disabilities (PDD) failed to pass that information on to Wolski's employer, a revelation that enrages her family.

"It's pure anger and it is still raw as the day that it happened," said her sister, Theresa McGregor. She wants to know why the house lacked a panic button, a safe room and video surveillance. The family also questions why Wolski, who was four feet nine inches tall, was left on her own to care for Saddleback, who stood six feet five inches and had a history of violence.

"I would do the math," Liz McGregor said. "I would say a man that size needs to be in there with him. Not that little, tiny girl, or woman. Shouldn't have happened."

System 'broken'

As Wolski's family sit around the table of their Calgary home, the pain of their loss is palpable.

Doug McGregor says he is having a difficult time dealing with his sister's death. (CBC)

"I'm having a hard time dealing with this," said her oldest brother Doug McGregor. "I'm not a wimp, I'm not a wuss, but my sister meant everything to me."

Wolski was smart, educated, articulate and friendly, her sister said. She loved people and wanted to make a difference.

"She liked everybody," said her mother Liz McGregor. "She just was for the underdog or everybody that had less than her.… Compassionate, caring, giving, you name it. All those attributes belonged to Val."

Details about what happened that night were kept under wraps for several months.

The psychiatric report that helped the judge decide Saddleback was unfit to stand trial was sealed by the court.

Earlier this month, lawyers for CBC News were able to convince the judge to release the entire document, which revealed details of how Wolski was found the morning of Feb. 13 by a worker who arrived at the house to relieve her.

The family says they don't blame Saddleback. Instead, they blame whomever put Wolski in that position. They are also angry that nearly everything they have learned about her death has come through media reports.

Terrence Saddleback is helped out of an armoured van at the Camrose, Alta., courthouse on March 2, 2011. (CBC)

"It erodes confidence in the system every time stuff like this happens and nobody steps up to say it's my fault or I'm sorry," said Wolski's other brother Cliff McGregor.

"You know that's all my mom would like to hear from somebody is, 'I'm sorry.' I'd like to hear it."

Doug McGregor is calling for the province to change a system the family believes failed Valerie and is failing her coworkers.

"It didn't break down, it's broken," McGregor said. "They have to revamp it."

McGregor said he wants to see what can be done to prevent another death: "You shouldn't have to die for $15 an hour."

Saddleback was remanded to Alberta Hospital, a psychiatric facility in Edmonton, after he was found unfit to stand trial. He is expected to remain there indefinitely.

With files from the CBC's Briar Stewart