Cauchi, armed with a knife, was shot dead by a police officer after he carried out the mass attack at a Westfield shopping centre in Bondi Junction on Saturday afternoon.
His parents Andrew and Michele Cauchi, who have expressed their sorrow for the victims and their devastation at their son’s actions, said Joel had been off medication for his mental illness.
Talking to reporters from outside their home in Toowoomba, Michele said the attack was out of character.
“He was brought up in love, he was a loved child,” she said.
“This is a parent’s absolute nightmare when they have a child with mental illness, that something like this will happen.
“My heart goes out to the people our son has hurt.
“If he was in his right mind he would be absolutely devastated.”
Andrew said he has been watching through vision from inside the shopping centre trying to understand what happened.
“This is so horrendous that I can’t even explain it,” he said.
“I don’t know why he would do this, I’ve done everything I can to help him.
“He’s my son and I’m loving a monster. For you, he’s a monster. To me, he was a very sick boy.”
Police have confirmed Cauchi was known to authorities due to his history with mental health-related issues.
He had recently moved to Sydney from Brisbane and NSW Police is working with Queensland Police in its investigations into the stabbing.
While the motive for the attack is still unknown, NSW Police Commissioner Karen Webb yesterday confirmed whether Cauchi targeted women was an “obvious line of inquiry”.
A dozen, including a nine-month-old baby girl, were seriously or critically injured and rushed to different hospitals around the city.
Poignant tribute left for victim as flowers grow at Bondi site
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