Differing medical opinions about what caused the death of a 20-month-old Aboriginal boy near Coolah have contributed to the delay of committal proceedings for the Geurie woman accused of killing the foster child, a court has heard.
Police charged the 42-year-old woman with murder in January 2018 and she has been remanded in custody since.
The boy died at a Neilrex property in March 2015 and the woman, whose identity the court has prevented from being disclosed, has not entered a plea.
Forensic pathologist Professor Tim Lyons conducted an autopsy and said multiple injuries to the boy's body were "inconsistent with being accidental in nature".
Professor Lyons said he believed there were a number of applications of blunt force trauma to the boy's head.
In the first part of a committal hearing in May, paediatrician Susan Marks said she believed head injury was "the more prominent cause of death".
In Dubbo Local Court on Tuesday defence barrister Ian Nash said after Professor Lyons died in June, another pathologist produced a report which indicated the boy's cause of death had "significantly changed from multiple head injuries to [being] the consequence of perforation of the stomach".
Mr Nash told the court an earlier report had suggested the boy's stomach perforation was caused by failed resuscitation attempts.
He said the defence team sought further expert opinion from a pathologist in Canada, who asked to see microscopic slides of tissue from the boy's body.
"We haven't been able to give him everything he needs," Mr Nash said.
The Crown and coroner had been contacted twice and asked to help provide material to the pathologist in Canada.
"We've had the answer 'no'," Mr Nash said.
Crown Prosecutor Liam Shaw told the court the material could be accessed in Australia and it would be "extremely expensive" to email it in a format that would allow it to be magnified and examined appropriately by the pathologist.
Mr Nash said the defence team hoped to avoid having the pathologist travel from Canada to examine the material, but he told the court there was a shortage of forensic pathologists in Australia.
A subpoena would be sought from the court "if there's no resolution to the slide issue", Mr Nash said.
The Crown and defence team agreed the case should be adjourned again for two weeks.
"We hope by then the logistical difficulties getting materials to the pathologist will be ironed out," Mr Nash said.
Magistrate Gary Wilson adjourned the case to November 19, when the woman will appear via audiovisual link.