Erin Patterson allegedly vented to friends she wanted nothing to do with her husband’s estranged family and called him a “deadbeat” months before serving up a poisonous lunch, a jury has been told.

“This family, I swear to f—ing god,” a message sent by an “Erin Erin Erin” account, extracted from a phone seized from Patterson’s home, said.

Messages that prosecutors allege Patterson sent to her Facebook friends in December 2022, as a child support issue with Simon Patterson continued, were aired in her triple-murder trial on Thursday.

The 50-year-old is accused of deliberately poisoning her former in-laws, Don and Gail Patterson and Heather Wilkinson, by serving up a death cap mushroom-laced beef Wellington in July 2023.

All three died in hospital days after the meal, while Heather’s husband Ian was the only surviving lunch guest.

Patterson has pleaded not guilty to three counts of murder and one of attempted murder, and claims it was a terrible accident.

She wore a paisley top and glasses on Thursday and stared at a screen in front of her, as Facebook Messenger conversations on a phone police seized from her home were read out to the jury.

The first message, on December 6, 2022, said Don had contacted her saying he wanted Patterson to get together with Simon and “pray for the children”.

“This family I swear to f—ing god,” the message said.

“I said to him about 50 times yesterday that I didn’t want them to adjudicate. Nobody bloody listens to me.”

The next day, another message from the Erin Erin Erin account said Don rang her overnight to say he thought there could be a solution to the issue if “Simon and I get together and try to talk”.

“Simon had indicated there was a solution … if I withdraw the child support claim! My head nearly exploded and I was like what?

“Don goes ‘oh sorry just ignore what I said I don’t want to get involved’.”

The message said she wanted Simon to be held accountable and then: “I’m sick of this shit, I want nothing to do with them.”

“I thought his parents would want to do the right thing,” the message continued.

Another message from the chat said she did not want to read messages sent the day before from Simon or his parents.

“Simon’s will be horrible, gaslighting and abusive, and it will ruin my day, and his parents’ will be more weasel words,” the message said.

“But by refusing to hold Simon to account they’ve made it clear his word’s more important than mine.

“They’ve never once picked up the phone to me since the separation so that tells me their choices.”

Two days later, on December 9, Erin Erin Erin sent another message to the chat.

“His mum was horrified I had claimed child support, why isn’t she horrified that her son is a deadbeat, and that had no choice but to claim,” the message said.

The jury was then shown images of mushrooms on trays, inside a dehydrator and on top of scales, taken in May 2023. They were found on a Samsung tablet seized by police from Patterson’s home.

Online descriptions from websites discussing ovarian cancer and “is it common for lymphoma to spread to the brain” from May 2023, which were also found on the seized tablet, were shown to the jury.

Before jurors were sent away they were shown a report outlining four factory resets were done on another phone, which prosecutors alleged Patterson had handed to police.

These included a factory reset of the phone on February 12 and again on August 2, 5 and 6 in 2023, the report showed, with the final “wipe” completed remotely.

The trial before Justice Christopher Beale will continue on Friday.