The ex-husband of the Australian woman who cooked up fatal mushroom lunch to her former parents-in-law, which left three people dead, has claimed she tried to poison him in 2022, according to a source close to the family.

Victorian woman Erin Patterson, 48, served the deadly fungi to four people on July 29.

Erin’s ex-in-laws, Don and Gail Patterson, and Gail’s sister Heather Wilkinson died after suffering symptoms consistent with poisoning by death cap mushroom.

Now a source close to Simon Patterson, the ex-husband of Erin, told the Herald Sun that Simon claimed Erin had tried to poison him through an “ingested toxin”.

The Herald Sun reported that the family friend said Simon felt “a bit off” and that his illnesses “often coincided when he spent time with her”.

Simon has refused to speak about the fatal lunch served up by his ex-wife in July, but in 2022 revealed on social media that he nearly died from a mysterious gut illness that left him in a coma.

A source close to the family has claimed Erin Patterson tried to poison her ex-husband Simon Patterson in 2022. Simon revealed he was in a coma after a mystery stomach illness.

“I collapsed at home, then was in an induced coma for 16 days through which I had three emergency operations mainly on my small intestine, plus an additional planned operation,” he wrote in May 2022.

“My family were asked to come and say goodbye to me twice, as I was not expected to live.”

He was in intensive care for 21 days before starting to recover.

“I’ve been feeling great for many days. I feel no pain, and it all seems to have no impact on my personality, character or anything else much,” the post read.

A source close to the family addressed the 2022 illness, telling the Herald Sun Simon thought he ingested poison “through nightshade plants”.

Erin Patterson’s ex-husband Simon Patterson posted on Facebook in 2022 that he nearly died from stomach issues and was in a coma for weeks. Photo / 7 News

Ex-husband pulled out of fatal lunch ‘at the last minute’

The latest allegations come after it was revealed Simon was invited to the deadly lunch but suddenly had to pull out “at the last minute”.

“Simon was supposed to go to the lunch but couldn’t make it at the last minute,” a friend of Simon told Daily Mail Australia on Wednesday.

Three people died, while a fourth person remains in a critical condition.

Police have spoken to Erin Patterson and confirmed she is being investigated, but have said she could be “very innocent”, news.com.au reported.

Erin did not suffer any injuries and neither did her two children.

Police say those children have been removed from her care as a “precaution”.

“The 48-year-old is [a suspect] because she cooked those meals for those present. She hasn’t presented with any symptoms,” Homicide Squad Detective Inspector Dean Thomas said.

“We have to keep an open mind. It could be very innocent, but we just don’t know at this point”.

Erin also spoke to media on Monday, outside the home where she served the fatal meal.

“I’m devastated, I loved them,” she said, appearing to be highly distressed.

“I can’t believe this has happened and I’m so sorry that they have lost their lives.

“I just can’t believe it.”

Don Patterson and Gail Patterson, Erin's former in-laws, died following a suspected mushroom poisoning. Photo / Supplied

On Thursday, 7 News Australia claimed Erin told police during the interview that she purchased the mushrooms from a local shop in the Leongatha area in Victoria.

However, so far there has been no recall or any warnings given for any locally-purchased produce, according to 7 News Australia, raising suspicions over the information Erin had originally given police.

The latest interview revelation comes as a food dehydrator was reportedly found at the local rubbish tip. It is now being tested by police to see if it is linked to the incident.

Veteran crime writer John Silvester, who has authored a number of best-selling books on crime in Melbourne, said he found one key element of the tragedy “slightly curious”.

Heather Wilkinson and pastor Ian Wilkinson. Photo / Supplied

“We’ve got the dehydrator from the house that was apparently found in the tip,” he told 3AW radio.

“It’s been reported the dehydrator was disposed of the day after the luncheon, which is slightly curious because the people had just presented to hospital with gastro-like symptoms.”

“I don’t think anybody at that point would be calling it a poisoning. People had got a bit crook.

“That’ll have to be tested to see whether or not it was operational, had it been tampered with, was it replaced or were there any remains within the dehydrator of death cap mushrooms.”

The investigation continues.