An inquiry into the convictions of Kathleen Folbigg for killing her four children has heard the diary entries used to convict her are now considered by experts to be the coping mechanism of a grieving mother.
The 55-year-old — who has been referred to as the country's worst female serial killer — was convicted in 2003 of three counts of murder and one of manslaughter.
She maintains her children died of natural causes over a decade between 1989 and 1999 in the New South Wales Hunter Valley.
Today, the second inquiry into her convictions resumed, after a petition from scientists about a recently discovered rare gene mutation that causes heart problems and sudden death.
The mutation has been found in Folbigg's two daughters, Sarah and Laura, but not in her two sons Caleb and Patrick.
When the inquiry opened in November 2022, two Danish professors gave evidence about the gene and how it can cause death in young children.
In her opening address, counsel assisting, Sophie Callan SC, said that, over the next three weeks, the inquiry would look at more scientific evidence that supports their research.
"The calibre of these experts needs to be recognised," Ms Callan said.
"The inquiry now has before it a weighty body of work from a range of cardiac and genetic experts, addressing the pathogenicity of the CALM2G114R variant identified in Ms Folbigg and her two daughters."
Ms Callan said the diary entries that were used to convict Folbigg in 2003 would also be scrutinised.
The inquiry heard that, at her criminal trial, the Crown "characterised" Folbigg's diary entries about struggling with motherhood as "admissions of guilt".
However, the inquiry heard, a range of experts who have since analysed them have a different view.
Ms Callan said expert psychiatrists and psychologists would give evidence that the diary entries were a coping mechanism written by a grieving mother with marriage problems and limited social support.
The inquiry heard that one expert, Dr Yumna Dhansy has found the diary entries suggest someone with complex post-traumatic stress disorder, and a grief disorder, but not a borderline personality disorder.
Ms Callan said another witness, Dr Kerri Eagle, has found the diary entries suggest "maternal grief following the death of children" and "a coping mechanism" but "nothing about guilt".
Witness Dr Joanna Garstang is expected to outline how self-blame and guilt following death is common, but the diary entries were "expressions of self-blame, not admissions of guilt".
Folbigg was convicted in a case based on circumstantial evidence.
The Crown case was that she smothered her children on separate occasions over a decade.
She has five years left to service of a 25-year sentence.
