In November 2017, Jemma Victoria Lilley, 26, and Trudi Lenon, 43, were found guilty of murdering 18-year-old Aaron Pajich.
The two women were convicted of luring Aaron, a teenager showing signs of autism, to their home and fatally stabbing him to death in June 2016. Aaron's body would ultimately be found in Jemma Lilley's backyard, the fresh dirt of the 'grave' covered by new cement and red tiles.
Mother of 3, Trudi Lenon, is reported to have known 18-year-old Aaron through her teenage son, and to have studied with him at a local college.
All reports indicate Jemma did not know Aaron before the incident.
During the sentencing, the court saw a series of Facebook messages in which Lilley referred to herself by SOS, an acronym for Son Of Sam, a serial killer she was obsessed with and Lenon went by Corvina, her BDSM name. These messages allegedly spoke of plans and fantasies of killing, torture and domination.
Jemma has remained a key focus of this investigation and public interest due to both her young age and her well-publicised love of serial killers.
This week, Seven's Sunday Night reporter Steve Pennells investigates what drove a then 23-year-old to take an obsession with violence and the macabre to the next level, costing Aaron Pajich his life.
A lonely childhood
Roland Hulka was a close family friend of Lilley's father and a father figure for Jemma once she migrated to Australia from the UK at the age of 18. Hulka spoke to the The West about Lilley's past and the moment he found out she had been arrested for murder.
Hulka revealed Lilley, who was born and raised in the UK was diagnosed with dyslexia and autism aged at just six, and that as a young child, Lilley's father removed her from her mentally ill mother's care "because of the trauma she had gone through."
Following this, Lilley's father often worked long hours and left the young girl alone. Lilley's one-time stepmother even fled the family due to a fear of a then-teenage Lilley, who was "terrorising" her and by then was "obsessed with serial killers, torture and death".
At 18, Lilley came to Perth on a working visa and stayed with Hulka, who was shocked at the woman the little girl he used to know had become. "She seemed a lot different when she came over," Mr Hulka told The West.
"She had lost that glow and that smile. It was daunting, and at one stage a little bit creepy — she was a stranger in a strange land."
Hulka also shared that Lilley had been married to a friend's older brother during her time in Australia to acquire a resident visa, however that marriage came to an end when he husband died in a car accident.
"She went across to England for a holiday and didn't want to come back to Australia, but her father pushed her to come back," Mr Hulka shared.
"I think if there were different choices made ... none of this would have happened."
Seven'S Sunday Night spoke with members of Jemma's family, including her former stepmother and her father, for a fresh investigation on what could have driven Jemma to take a life.
Digging deeper into Jemma's childhood during the segment, Jemma's father revealed her mother suffered a "mental breakdown and joined a spiritual cult." It was following this that a young Jemma developed an obsession with extreme violence, her unusual fixation prompted many to assume she had "a mental problem."
The manager of a video shop which Jemma had frequented also discussed her past dealings with a then 20-something Jemma, sharing that the young woman who exclusively rented horror movies divulged she had growing urges to kill and wanted to take a life by the time she was 25-years-old.
It was following this Jemma met Trudy Lennon and together they brought a plan to commit murder to life and it was teenager Aaron Pajich-Sweetman that paid the ultimate price.
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