What started as a simple disagreement over a birthday party invite has now become a key piece of evidence in one of Australia’s most shocking murder trials.
Erin Patterson is currently on trial, accused of killing her former in-laws — Don and Gail Patterson — and Gail’s sister Heather Wilkinson.
The case has gripped the nation ever since the three family members died after eating a meal allegedly prepared by Erin at her home in Leongatha on July 29, 2023.
The dish in question? A beef Wellington laced with deadly death cap mushrooms.
A Fractured Marriage and a Tense Text Exchange
In court on Friday, Simon Patterson — Erin’s estranged husband — returned to the witness stand.
The jury was shown text messages exchanged between Simon and Erin on October 14 and 15, 2022, which revealed simmering tensions between the pair.
The texts centered around an invite — or rather, a late invite — to Simon’s mother’s 70th birthday party.
Erin wasn’t happy. She called the invite “an afterthought” and accused Simon’s family of forgetting about her.
“I might pass thanks,” she wrote, “What I reckon is everybody forgot to actually invite me… I feel very, very hurt about that.”
Simon, trying to smooth things over, assured her his parents did want her there.
“I ask that you consider Mum’s feelings. They’d love you to be there,” he replied.
Eventually, Erin agreed to attend with their two children.
Simon Opens Up About Erin’s Mental Health
During his testimony, Simon gave some emotional insights into Erin’s mental state during their marriage.
He said she had struggled with mental illness, particularly post-natal depression following the birth of their son.
Appearing visibly emotional, Simon recalled the overall strain in their relationship.
At the time of his mother’s birthday, he said, there was “a lot of tension.”
Erin, dressed in a brown jumper, reportedly glared at Simon from the dock as he gave evidence.
A Tearful Moment Watching a Family Video
At one point during Friday’s proceedings, Simon broke down in tears when shown a touching family video titled “Rocket Car.”
The clip showed his late father, Don, conducting a lighthearted science experiment with his grandson.
While the attempt at powering a toy car with a small rocket didn’t go quite as planned, the moment brought both laughter and tears to the courtroom.
“It’s working but why isn’t it going?” someone could be heard saying, prompting Simon to smile through his tears.
Erin’s Deep Distrust of Hospitals
Another focal point in the case has been Erin’s aversion to hospitals — something Simon confirmed had been a consistent issue throughout their relationship.
The jury heard that even after the deadly lunch, Erin was reluctant to stay at the hospital.
She texted Simon expressing frustration with doctors, saying, “They’re arguing with me now… this doctor is not listening to me and being a bit mean about it.”
In another message she wrote, “I’m going to Clayton.
Squeaky wheel.” She also described symptoms like nausea and abdominal pain.
Her children, too, reportedly had traumatic hospital experiences, including a botched X-ray for their son and a distressing tube insertion for their daughter.
Alleged Lies About Health and a False Cancer Claim
One of the prosecution’s most startling allegations is that Erin invited her in-laws to lunch under the pretense of discussing a cancer diagnosis — one the prosecution claims was completely fabricated.
Simon told the court he had never heard Erin mention anything about ovarian cancer before.
He did say she had once told him about a possible multiple sclerosis diagnosis and also suffered from sleep apnoea, but never raised serious concerns he found suspicious at the time.
More Bickering Over Bills and Child Expenses
The jury was also shown more examples of the couple’s ongoing arguments in the months leading up to the alleged poisoning.
In one message from November 2022, Erin asked Simon to cover a bill from their son’s surgery.
“Can you please pay this?” she asked, referencing an anaesthetist’s fee.
But Simon responded that he had been instructed by the Department of Human Services not to pay additional expenses beyond child support.
Erin insisted the money wasn’t for her, but Simon stood firm, saying he didn’t want to create confusion or conflict.
Reaching Out to the In-Laws for Help
At one point, Erin apparently went directly to Simon’s parents to talk about her struggles, prompting another sharp exchange between the exes.
Simon messaged Erin: “Mum and Dad told me you asked them over.”
He claimed the issues raised were about their son’s well-being and financial matters related to their children.
Frustrated with their lack of progress, Simon said he suggested bringing in a mediator to help improve communication.
He described Erin’s tone as “extremely aggressive,” making it hard to have constructive conversations without third-party support.
Courtroom Continues to Hear Shocking Details
Simon’s testimony is set to continue next week. Before dismissing the jury for the day, Justice Christopher Beale reminded them not to discuss the case or seek information about it outside the courtroom — a standard but serious warning in a trial so highly publicized.
As the trial continues, the country waits to learn what really happened during that now-infamous lunch — and whether the truth will finally come out.