A three-year-old boy rushed to an Edmonton hospital on the weekend died of head injuries, shows an autopsy report released Tuesday, when his foster mother also appeared in court on a second-degree murder charge.

The child was taken to Stollery Children's Hospital from a west-end home early Friday, and died Saturday. The 32-year-old foster mother charged in connection with his death can't be named under Alberta's Child, Youth and Family Enhancement Act.

Court documents filed by the Edmonton Police allege the foster mother committed assault causing bodily harm on the little boy from Dec. 5 — the day she began to care for him — until Friday.

She is also charged with unlawfully abandoning or exposing the child to danger on Thursday, the day before he was taken to the hospital.

The autopsy showed the child died of cranial trauma.

The foster mother, who was in leg shackles and handcuffs, showed no emotion during her Tuesday morning court appearance.

"She's coping as well as she can, but she's having a very hard time," said her lawyer, Shannon Prithipaul. "Her family is backing her 100 per cent, and she has friends in the community and they're all very concerned about her."

The single mother was working part-time and had two children of her own.

She had become a foster parent less than two months ago, and had taken in two foster children. Alberta Children's Services have taken all the children into protective custody.

No warning signs, union leader says

Government workers did not spot any warning signs in this child's case, said social worker Maureen Braun, chair of Alberta Union of Provincial Employees Local 006, which represents child-care, family and social workers.

"Everything seemed normal," Braun said. "Right now people are so traumatized by this whole incident. You do the best you can during the day and hope that children are safe."

Alberta has 10,249 children in care. Braun said there are simply too few foster parents for too many foster children, and social workers are left scrambling to try to hold the system together.

"The workload is very heavy. The cases are very complex. The turnover for front-end staff is very high. They're not staying because of the heavy case load."

'Social workers feel overburdened'

Weslyn Mather, Alberta Liberal critic for children's services, said the average social worker is handling more than double the expected caseload, leading to predictable problems.

"The social workers feel overburdened, go home thinking 'I didn't do everything I should have done today or I didn't pay enough attention to this because of this other factor I had to deal with.' So there is burnout."

Katherine Jones, director of the Alberta Foster Parent Association and a foster parent herself, said the child's death left her in shock.

"It made me feel ill. And I thought, how can this happen in this system that has been created specifically to ensure the safety and well-being of children?"

Children's services minister calls review

Children's Services Minister Janis Tarchuk called the tragic death an isolated incident, but she is looking for answers about what happened and to determine whether the system is overburdened.

"I think these are all very, very important questions, but that's exactly why I chose to ask for the special case review, because I do think having a review of the system is what's going to be very helpful in helping all of us understand the situation."

Tarchuk could not say how long the review will take to complete.