Erin Patterson (C) leaves the Supreme Court of Victoria in Melbourne, Australia, on Monday, when she was sentenced to three life sentences plus 25 years. Photo by Joel Carrett/EPA

Sept. 8 (UPI) -- Erin Patterson, the Australian mother convicted last month of killing her estranged husband's parents and aunt by serving them a dish containing poisonous death cap mushrooms, was sentenced to three life sentences plus 25 years for attempted murder on Monday.

The sentences are to be served concurrently with a non-parole period of 33 years, Justice Christopher Beale of the Victorian Supreme Court said during sentencing, which was broadcast live.

"Fixing a non-parole period is not to undervalue the horrendous nature of your offending," he said. "Your total effective sentence will be life imprisonment and the period during which you will be ineligible for parole will be a very substantial one."

Patterson, 50, was convicted by a jury in July for killing Gail and Don Patterson, the 70-year-old parents of her now ex-husband, Simon Patterson, and his 66-year-old aunt, Heather Wilkinson, and attempting to kill Heather's husband, Ian Wilkinson, on July 29, 2023.