NSW Health provided DNA samples from each of the children to the inquiry and Folbigg consented to providing a swab, counsel assisting the inquiry, Gail Furness, SC, said on Monday at the start of the inquiry at Lidcombe Coroners Court.

A multidisciplinary panel of experts will provide a report to inquiry chair and former District Court judge Reginald Blanch "in light of the significant advances relevant to the scope of the inquiry", Ms Furness said.

Human Genetics Society of Australia president and NSW Health South Eastern Area Laboratory Services clinical director Dr Michael Buckley will also give evidence.

The inquiry was told Folbigg will give evidence about damning entries in a diary she kept during the period her babies Caleb, Patrick, Sarah and Laura died at Singleton between 1989 and 1998.

The entries included comments like "She left, with a bit of help", about the death of Sarah in 1993 which a judge later said "made chilling reading".

Folbigg's lawyer Isabel Reed on Sunday said her client would not be attending the inquiry in person. Folbigg is following proceedings via an audio-visual link from jail. It has not been confirmed if Folbigg will give evidence in person. Her evidence is not expected until the second part of the inquiry in April.

The inquiry will hear evidence this week from paediatric forensic experts Professor Stephen Cordner, Professor Johan Duflou and Professor John Hilton in broad agreement that there is no evidence "from a forensic pathology viewpoint to suggest that any of the children had been killed, let alone smothered".

NSW Attorney-General Mark Speakman announced the inquiry in August, 2018 after Newcastle woman Helen Cummings launched a campaign in 2011 for a review of Folbigg's murder and manslaughter convictions in 2003.

It followed the release of academic Emma Cunliffe's book, Murder, Medicine and Motherhood, which raised serious questions about the Folbigg convictions.

The University of Newcastle Legal Centre in 2013 agreed to investigate the issues raised. In June, 2015 the centre presented a petition for a judicial review to the NSW Governor.

Mr Speakman announced the inquiry after acknowledging there were questions about whether the case against Folbigg had been established beyond reasonable doubt, after a jury in 2003 was told there were no recorded cases of three children in one family dying of sudden infant death syndrome, or SIDS.

In a summing up the Crown told the jury: "It has never been recorded that the same person has been hit by lightning four times" and "I can't disprove that one day some piglets might be born with wings and that they might fly. Is that a reasonable doubt?"

The information about no recorded multiple SIDS cases in one family was incorrect, the inquiry heard.

"It is clear from the work of the inquiry that before 2003 there had been reported cases involving the deaths of three or more infants in the same family attributed to unidentified natural causes, or at least not established as attributable to unnatural causes," Ms Furness told the inquiry.

This included a 1986 report of five baby deaths in one family, the inquiry heard.

A New Zealand paediatrician and baby sleep expert, Professor Dawn Elder, is giving evidence.  

Folbigg was sentenced to a minimum 25 years' jail for the manslaughter of her first child Caleb, 19 days old, and the murder of her three children Patrick, eight months, Sarah, 10 months, and Laura, 19 months, at Singleton between 1989 and 1999.

Each child died suddenly and unexpectedly because of "cessation of breathing", although post-mortems failed to establish the reason.

The inquiry was told Mr Blanch will prepare a report to the Governor, but if he believes there is reasonable doubt about the guilt of Folbigg, he may refer the matter to the NSW Court of Criminal Appeal to consider if the convictions should be quashed.

Barrister for Folbigg, Jeremy Morris, SC, told the inquiry there was "a massive amount of material" that formed part of the Folbigg brief.

The hearing, that will run this week, continues.    

Newcastle Herald