Toronto — Jeffrey Baldwin was beaten with a stick by his grandmother because he was not cleaning his feces-stained bedroom fast enough his older sister testified.

In a videotaped statement played to a hushed courtroom on Wednesday, the young girl -- whose name cannot be released -- recounted how the bedroom that she and her brother were locked into each night became their bathroom.

She said their grandmother, Elva Bottineau, would make them help her clean it up. But if they "weren't working fast enough," Bottineau would hit them with the handle of a mop, she told Det. Kimberley O'Toole.

She said sometimes she and Jeffrey would be in their cribs when they were hit.

"What would Jeffrey and (his sister) do when that happened?" asked O'Toole. "They'd cry," Jeffrey's sister said.

Bottineau, 54, and her 53-year-old common-law husband Norman Kidman are on trial for first-degree murder in relation to their grandson's death three years ago. Both have pleaded not guilty.

The girl described to investigators how Jeffrey was called a "pig" by his grandparents and sometimes told to "stand in the pig corner."

She said the young boy spent most of his time locked in his room and how they both had "bad things" done to them. Those things included forcing the children to dig through garbage to find food and drinking from the toilet.

Jeffrey's other grandmother had been banned from seeing the child. After watching the videotape, Susan Dimitriadis was overwhelmed by what the children allegedly experienced.

"I didn't realize how bad it was for them," said Dimitriadis.

At the time of his death, Baldwin was too weak to stand up. On the videotape his sister told what happened.

"The first time he came down the stairs … my grandma placed him at the table and he fell down. And my grandpa started yelling at my grandma and … my grandma thought he was just being lazy, but my grandpa said the kid doesn't get enough exercise," the young girl says on videotape.

According to the sister, they brought him milk, however, it was not enough. Jeffrey died soon after. He reportedly weighed 21 pounds. A healthy six-year-old normally weighs twice that much.

Jeffrey had been placed in his grandparents' custody by the Catholic Children's Aid Society -- despite Bottineau having been convicted in the death of her infant daughter and Kidman's record as a convicted child abuser.

In fact, a children's aid assessment of Bottineau conducted in 1970 described her as an "incompetent parent who was a danger to herself and others."

The agency had seized Jeffrey and his sister while it probed abuse allegations against their parents in 1998.

The society has since admitted mistakes were made in the case, and has changed its screening policy for family adoptions.