When Kathleen Folbigg was 15, she learned the truth about her family's dark history.

Kathleen Folbigg's life is one scarred by death. It's the reason Australians know her name. It's why she spent 20 years in prison and was once - incorrectly - dubbed "Australia's worst female serial killer".

Yesterday, Folbigg was pardoned and immediately freed from prison after a report from NSW chief justice Tom Bathurst KC on Friday stating that there is "reasonable double as to Ms Folbigg's guilt". 

But nothing will make up for the years she has suffered behind bars - or the difficult and dark family history that is an integral part of her story. 

Between 1989 and 1999, the NSW woman gave birth to four children, none of whom lived to see their second birthday.

The tragedies were first attributed to natural causes including Sudden Infant Death Syndrome and epilepsy. But in 2003, a jury determined beyond reasonable doubt that Kathleen Folbigg was guilty of murder, accepting the Crown's case that she smothered her children in fits of frustration and resentment.

For years, that verdict was called into question. In 2021, a collective of 90 leading scientists, including two Nobel laureates, signed a petition to the NSW Governor pointing to recent medical and scientific discoveries that cast doubt over Folbigg's guilt. 

And finally, yesterday, Folbigg was pardoned and freed. 

Throughout the coverage of this enduring case, a story has emerged of a complicated life, one that was scarred by yet another death years earlier; a death that not even Kathleen Folbigg knew about until she was a teenager.

Listen to journalist Jane Hansen's full conversation with Mia Freedman about Kathleen Folbigg's life and crimes on No Filter. Post continues after.

Kathleen Folbigg's childhood.

Kathleen Folbigg was raised by Deirdre and Neville Marlborough in Kotara, a suburb in the NSW coastal city of Newcastle. Folbigg knew them to be her adoptive parents, but at around the age of 15, she learned otherwise.

Not only was she simply the Marlborough's foster child and therefore technically still a ward of the state, she had entered the foster system as a toddler after her father murdered her mother.

Speaking to Mamamia's No Filter podcast, journalist Jane Hansen painted a picture of Folbigg's father, a Welshman named Thomas John Britton.

"Britton was a stand-over man and a wharfie. He had already attempted murder on the woman he was with beforehand; he'd slashed her throat, and he'd spent some time in jail. And then he met Kathleen Donavan, Kathleen Folbigg's mother," she said. 

When Folbigg was about 18 months old, her mother walked out, leaving her in the care of her violent father. 

On the night of December 8, 1968, Britton tracked Donavan down in the Sydney suburb of Annandale and stabbed her 24 times. She died in the street.

Hansen is the host of Mother's Guilt, a podcast that deep-dives into the Folbigg case. 

In episode one, she spoke to Folbigg's childhood friend, Tracy Chapman, who recalled how Folbigg reacted to the revelation about her past and the fact she was not legally part of the family in which she had been raised.

"There was a lot of soul searching," Chapman said. "She didn't talk much about it. She matter-of-factly told us what was going on..."

It's understood that the discovery escalated tension within the Marlborough household, and Folbigg ultimately left at age 17 to live with her schoolfriend, Billi-Jo Bradshaw, and Bradshaw's mother.

"She was tough, which is something that I needed," Bradshaw told Hansen. "I was bullied a lot at school... she would stick up for me and tell people off and just protect me... She was always there for me."

Folbigg's tenancy there didn't last long. Months later, she attended a disco in Newcastle where she locked eyes with a 24-year-old man named Craig Folbigg.

"She met him, and that was it," Bradshaw said. "She was just taken by him. She wouldn't shut up about him, about how wonderful he was. I think that's what she was looking for, too; someone who she thought was reliable and would love her unconditionally."

The couple were married two years later in 1987 and shortly after had their first child, Caleb. He lived just 19 days. Their second, Patrick, lived 8 months. Their third, Sarah, lived 10, and then came Laura who lived 19 months. 

In each case, the child stopped breathing. In each case, it was Folbigg who found them.

She maintained her innocence until the very day she was finally freed. 

"I am my father's daughter."

During Folbigg's trial, the Crown leaned heavily on her diary. Pages of stream-of-consciousness scrawling about her life, her relationship, her struggles as a parent and her grief.

One phrase, in particular, stood out. It was from an entry in 1996, before she fell pregnant with Laura.

"Children thing still isn't happening. Thinking of forgetting the idea. Nature, fate and the man upstairs have decided I don't get a 4th chance. And rightly so I suppose. I would like to make all my mistakes and terrible thinking be corrected and mean something though. Plus I'm ready to continue my family time now. Obviously I'm my father's daughter. But I think losing my temper stage and being frustrated with everything has passed. I now just let things happen and go with the flow. An attitude I should of had with all my children. If given the chance I'll have it with the next one." [sic]

Those words were withheld from the jury in the 2003 trial, along with the fact that her father had killed her mother — a ruling by the judge designed to prevent the jury from forming the 'illegitimate view' that Folbigg had inherited a propensity to murder. But after her conviction, the passage (and others) has been widely interpreted as an admission of guilt.

In a 2019 inquiry into her convictions, Folbigg attempted to explain those words.

"I believed and thought, at the time, that my father's actions ruined my life and my life never seemed to go right from there. And it was a thought of, along the lines of, sins of the father being on the daughter. Was I paying the price?" she said.

At the conclusion of that inquiry Former Chief Judge of the NSW District Court Reginald Blanch said he did not have "any reasonable doubt" as to Folbigg's guilt.

That all changed this week. 

As a free woman, we can only hope, despite all she has endured, Folbigg can find peace. 

For more No Filter, go to mamamia.com.au/podcasts/no-filter.

Feature image: AAP.

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