A man accused of murdering a young Toronto woman and burning her remains in a massive animal incinerator had been telling people in the weeks before her disappearance that he was buying the large piece of equipment to start a mobile pet cremation business with his uncle, a court heard Thursday.

But that uncle, veterinarian Robert Burns, emphatically told jurors at Dellen Millard's trial that his nephew never asked him to launch such a business, calling the idea "absurd."

"It is horrible," Burns said. "Can you imagine driving up to a strip mall, carting out cadavers and lighting up the incinerator with embers flying out right there in the parking lot? Then driving down main street to the next clinic?"

Millard, 32, and his co-accused Mark Smich, 30, are accused of killing Laura Babcock in 2012. They have pleaded not guilty to first-degree murder.

The Crown alleges the pair killed the 23-year-old because she was the odd woman out in a love triangle with Millard and his girlfriend. Millard, who is representing himself, has said, however, that he didn't care about the animosity between the two women.

Prosecutors allege Millard and Smich burned Babcock's body in an animal incinerator -- named The Eliminator -- several weeks after she disappeared in early July 2012. Babcock's body has not been found.

A forensic anthropologist has testified that a photograph of the incinerator's interior shows objects that look like human bones. The incinerator -- which court has heard was capable of cremating a 225-kilogram animal -- was found on Millard's farm in Waterloo, Ont.

Millard's uncle said he heard of the purported mobile pet cremation business through a mutual acquaintance in the summer of 2012.

"At the time he told me Millard had bought a monstrous animal incinerator and told me I was going into business with Millard," Burns testified. "It was the most absurd thing I ever heard of."

Burns said he'd never go into that line of business with Millard as the two stopped talking regularly sometime in 2002.

They did speak twice in 2012 after Burns heard talk of the pet cremation venture, with Burns "laying in wait" for his nephew to bring up the business, but the subject wasn't raised, he said.

"Just the useless drivel that came from his mouth, but never about the incinerator," Burns said when questioned by a Crown lawyer, adding that he didn't want to be the one to raise the issue.

Burns' animosity toward his nephew burst forth on several occasions when being cross-examined by Millard, leading to several cautions from the judge presiding over the case.

After several back-and-forth questions about whether Burns had visited Millard's home to treat his father's cats, Burns lost his temper.

"I have to be very clear that this tragic and diabolical affair, I have one role in it," Burns said, his voice rising as he stared at his nephew.

The outburst prompted an intervention from the judge.

"The personal commentary is completely forbidden, you must stop that," Justice Michael Code said to Burns.

Court also repeatedly heard Millard call the relationship with his uncle "distant."

"Robbie, we already outlined our relationship is distant, that's clear right now in the courtroom, would you agree with that?" Millard asked at one point.

Burns took a long pause, a deep breath and looked around the courtroom before returning his gaze to his nephew.

"That would be an understatement," he said.