One of the last people who saw Jeffrey Baldwin alive said the five-year-old was so weak and malnourished that as he crawled upstairs to his cold, fetid bedroom in a slow "death march," his pyjama bottoms fell down with each step.

By the time he starved to death Jeffrey weighed 21 pounds — one pound less than he did on his first birthday.

It's a disturbing scene that will always stick with retired Toronto police Det. Michael Davis, who investigated Jeffrey's death 11 years ago.

The Ontario Coroner has called an inquest into the death of Jeffrey Baldwin. (CBC)

"He was trying to make his way up the stairs, crawling up the stairs as his little pyjamas were falling off of the hips because he had no hips," Davis recalled from testimony at the trial where Jeffrey's grandparents were convicted of second-degree murder.

"You deal with it, but you don't forget it. That's what makes you angry, when you see something like this. What makes me even more angry is the fact that it could have been prevented."

Elva Bottineau and Norman Kidman were already convicted child abusers when they were granted custody of Jeffrey and three other grandchildren in 2002.

But the Catholic Children's Aid Society of Toronto did not find those records until after Jeffrey's death.

Bottineau had a Grade 8 education, an IQ of 69, and even by her lawyer's assessment was "wholly unqualified to raise children."

Major changes have been implemented at the CCAS and children's aid societies across Ontario since then, including increased family history, background and record checks. Relatives who become caregivers are also subjected to the same rigorous standards as foster parents and adoptive parents.

Child protection policies and practices are expected to be examined as part of the coroner's inquest into Jeffrey's death, which is set to start Monday.

Life sentences

Bottineau and Kidman were convicted in 2006 and sentenced to life in prison with no parole for 22 and 20 years, respectively.

Bottineau tried unsuccessfully to appeal her conviction up to the Supreme Court of Canada, and with the high court refusing last year to hear the appeal, the coroner's inquest could move forward.

Jeffrey died weeks shy of his sixth birthday, of septic shock from malnutrition and bacterial pneumonia that was caused by sleeping in his own waste.

A pediatric pathologist told Jeffrey's grandparents' trial that the boy developed pneumonia a few days before his death. Fecal bacteria got into his bloodstream, causing septic shock that would have made it difficult to breathe.

Experts at the trial likened Jeffrey's body to that of a starving child in a third-world country.

"He was just emaciated," said Davis, who is now a private investigator. "His ribs were exposed. I mean, just the overall appearance of him was horrific...I don't know what to think of those that may have seen that and just turned a blind eye."

Six adults and six children under 10 years old were living in the east-end Toronto home when Jeffrey died: Bottineau and Kidman, their daughter Tammy, her husband and their two children, another daughter, Yvette, her boyfriend James Mills, and Jeffrey and his three siblings — the children of the couple's other daughter, Yvonne, who lost custody of them.

Mills testified — reluctantly — at Bottineau and Kidman's trial and painted a grim picture of Jeffrey's life and the blatant abuse that no one reported.

For reasons that Davis still struggles to understand, Jeffrey and one of his sisters were treated worse than dogs, while the other children were apparently well looked after.

Siblings confined to filthy bedroom

Jeffrey and his sister were confined for up to 14 hours a day to their unheated bedroom, which was soaked with urine, stained with feces and littered with bags of filthy diapers throughout with no toys in sight, while the rest of the house was spotless.

The two children were called "pigs" and were forced to sit on a shoe mat in the "pigs' corner" and eat leftover scraps from bowls with their hands, court heard from a statement from Jeffrey's other sister.

It would have been clear to anyone who saw Jeffrey that he was in desperate need of help, the trial heard.

Months before Mills watched Jeffrey crawling up the stairs while his pyjama pants fell down, he saw the little boy spend more than 10 minutes struggling to go up the stairs to bed, he told police.

Mills said in a statement to police that he thought Jeffrey looked sickly from the first day he saw the boy, months earlier.

"It was almost like a death march," Mills said. "He was waiting to die."

Mills, who enjoyed free meals and board while living in the house with his girlfriend, admitted at trial that he didn't want to jeopardize his easy lifestyle by fighting for the emaciated boy's welfare.

Davis said people asked him at the time why every adult in that house wasn't charged. Bottineau and Kidman were charged with murder as well as forcible confinement for the treatment of Jeffrey's sister. Beyond that, Davis said he was bound by the Child and Family Services Act.

Under that law, everyone has a duty to report suspected child abuse, but the only people who could be found guilty of an offence for not reporting it are professionals working with children such as doctors and teachers.

A Crown lawyer told Bottineau and Kidman's trial that the couple routinely lied about Jeffrey's condition to doctors and emergency workers to cover their tracks. Kidman told police that Jeffrey wasn't sent to school because he wasn't toilet-trained and wouldn't have been accepted.

Bottineau and Kidman used the children as a source of income, collecting government support cheques in their names, the trial was told.

Jeffrey's siblings were taken into care after he died. The oldest sister would be about 19 years old now and Davis hopes they are faring all right.

"I've thought of it many times, wondered about them and how they're doing and how they're coping with it," he said. "The eldest one was showing a lot of guilt. I've always wondered about her and about Jeffrey's other sister...There's no doubt in my mind that she could have been a second victim."