A mother accused of murdering her two disabled adult children is alleged to have killed her son and daughter for a million-dollar insurance payout.
Maree Mavis Crabtree, 54, forced her then-18-year-old daughter Erin and 26-year-old son Jonathan to take prescription medication which caused an array of health and developmental problems and eventually led to their deaths, Australian police allege.
Erin was found dead in the Maudsland, Queensland, home she shared with her mother in September of 2012. Crabtree was reportedly on a cruise at the time.
Jonathan's body was found in his nearby Upper Coomera home five years later in 2017.
Detectives preparing a report for the coroner over Erin's 2012 death became suspicious after Jonathan's death and Crabtree was arrested in January 2018.
Detective Inspector Mark Thompson described the siblings' deaths as "premeditated and calculated, financially driven crimes", ABC News reported at the time.
Crabtree's committal hearing kicked off at Brisbane Magistrates Court on Tuesday, March 16.
The court was told the mother allegedly controlled her son's finances, refused to let him get a job and plied both him and his sister with prescription medication to benefit from disability payouts, news.com.au reports.
Crabtree's ex-husband Peter McMahon, who was not the father of the children, said he did not believe the siblings had any health issues when the pair were together between 2003 and 2008.
He said the children were all going to school as normal but noticed Erin's behavior "began to change" from being "talkative and outgoing" to not speaking to anyone when they moved to McCully's Gap in 2005.
"I tried everyday, I came in and talked to her ... she just wouldn't participate," he said. "She just didn't open her mouth, just nodding and shaking her head."
Cassandra Hopper, a friend of Jonathan's, gave evidence that he had told her his sister died of "cancer" and was "very distraught" over her death.
Hopper also told the court that Jonathan had told her his mother wouldn't let him get a job and he "wasn't able to live his own life." She added: "He had to live by her rules."
Jonathan's former girlfriend Katelyn Lofts told the court she thought Crabtree put something in a drink that caused her to feel groggy and fall asleep on three occasions, the Australian Associated Press reports.
Lofts also said Jonathan told her he was "petrified" of his mother and that he drove his car into a tree because he wanted to kill himself.
Crabtree's committal hearing is set to last for three weeks. The 54-year-old is facing 11 charges including murder, torture, attempted murder, fraud, attempted fraud and robbery in company and another eight counts of obtaining a financial benefit by deception.
