Erin Patterson told her estranged husband she wanted to make a “special meal” for his family before she allegedly fed them death cap mushroom-laced beef Wellingtons, a jury has been told.

Prosecutors are opening their case against 50-year-old mother Patterson as her trial began in the small town of Morwell, about 150km from Melbourne.

She has pleaded not guilty to three counts of murder over the deaths of Heather Wilkinson, Don and Gail Patterson, and the attempted murder of Ian Wilkinson.

One of the three people who died after consuming a death-cap mushroom dish wondered why Patterson’s plate was different to her own, a jury was told.

Wilkinson, who died after a July 2023 lunch at Patterson’s Leongatha home, asked questions about the meal as she started to become ill in the subsequent hours, prosecutor Nanette Rogers SC told a jury of 15.

“I noticed that Erin put her food on a different plate to us, her plate had colours on it, I wondered why that was,” Wilkinson allegedly said before her death.

Patterson invited her estranged husband Simon and his family around to her home for lunch, Rogers said. He declined to attend.

Patterson had already started preparing the lunch when her guests arrived about 12.30pm and she served their meals on four large, grey plates that were different to her smaller one, Rogers said.

She served up individual beef wellingtons, each consisting of a piece of steak covered with mushrooms and wrapped in pastry, served with mash potato and green beans, the jury heard.

The prosecution alleges the meals served to the four guests contained death cap mushrooms.

All became poisoned and attended hospital in the days after the meal.

“They said grace and started the meal, Ian and Heather ate an entire portion, Gail had half a serve and Don ate hers and his,” Rogers said.

“There was banter amongst them about how much they’d eaten.”

Patterson then revealed to the group she had cancer and asked their advice about giving that information to her children. They told her it was best to tell them.

A day earlier, Simon Patterson sent a text to his estranged wife to decline her invitation because he felt “uncomfortable”, but he said he was happy to talk about her health another time, Rogers said.

In her reply, Patterson allegedly “emphasised the effort she put into the lunch and said she wanted it to be a special meal and she may not be able to have a lunch like this for some time”.

She had organised for her children to be out of the house for the lunch, the court was told.

Within hours of the lunch, the guests started to suffer from diarrhoea and nausea, with Don and Gail Patterson first calling an ambulance that took them to Korumburra Hospital, Dr Rogers said.

Simon Patterson drove the Wilkinsons to the same hospital, but they were told it was at capacity and they went to Leongatha Hospital instead, she said.

All four were then transferred to hospitals in Melbourne as their conditions deteriorated, where health professionals found they might have ingested death cap mushrooms.

Simon’s brother Matthew called Patterson to ask where the mushrooms had come from, Rogers said.

“The accused said there were two sources of mushrooms, fresh ones from Woolworths and dried ones from an Asian supermarket in the Oakleigh area,” she told the jury.

She said Patterson was also called by a toxicologist, who asked for names of Chinese stores in Oakleigh she may have visited.

“She said she didn’t recall and it may have been in Glen Waverley,” Rogers said.

Patterson’s barrister Colin Mandy SC was due to give a reply on behalf of the defence after Rogers’ opening concludes on Wednesday afternoon.

‘Special meal’

Earlier, the court heard that Patterson told her estranged husband she wanted to make a “special meal” for his family before she allegedly fed them death cap mushroom-laced beef Wellingtons.

Rogers revealed Patterson wanted to hold the lunch to seek advice on telling her children about medical issues.

Patterson invited all of the guests to the meal, along with her estranged husband Simon, at a Sunday service at Korumburra Baptist Church, where Ian was the pastor, Rogers told the jury.

The day before, on July 28, Simon sent a text to Patterson declining her lunch invitation, because he felt “uncomfortable”, but was happy to talk about Patterson’s health another time, she said.

Rogers said Patterson, in her reply to Simon, “emphasised the effort she put into the lunch and said she wanted it to be a special meal and she may not be able to have a lunch like this for some time”.

Patterson organised for her children to be out of the house for the lunch on July 29.

After her former in-laws and Heather and Ian Wilkinson arrived at her home, Patterson served up individual beef wellingtons consisting of a piece of steak covered with mushrooms and wrapped in pastry, Rogers said.

She served wellingtons with mashed potato and greens and gave her guests four large grey dinner plates, while she ate her meal off a different small tan-coloured plate, the jury was told.

“They said grace and started the meal, Ian and Heather ate an entire portion, Gail had half a serve and Don ate hers and his,” Rogers said.

“There was banter amongst them about how much they’d eaten.”

After the main meal, the group tucked into a dessert of cake and a fruit platter, brought by Gail and Heather.

Patterson then revealed to the group she had cancer and asked their advice about telling her children. They told her it was best to tell them.

“They prayed for the accused’s health and wisdom,” Rogers said.

Patterson’s barrister Colin Mandy SC will give a reply on behalf of the defence on Wednesday afternoon.

Justice Christopher Beale told the jury witnesses will include Simon Patterson and Ian Wilkinson, as well as a number of medical experts, doctors and police.

Three attempted murder charges brought against Patterson regarding her husband have been dropped by prosecutors, Justice Beale told the jury on Tuesday.

The trial continues.

-AAP