Preliminary police investigations have found that Mrs Perinovic was responsible for all of their deaths.
“Homicide squad investigators have formed the preliminary view that the 42-year-old woman is responsible for all four deaths and on completion of their investigation, a report will be provided for consideration of the coroner,” police said.
Five-year-old Anna Perinovic had been due to start prep in weeks, joining her elder sister Claire at St Christopher’s Primary School in Airport West.
Instead, the school community has been left devastated by the tragic deaths.
“Our school community is deeply shocked to receive this heartbreaking news and extends sincere sympathy and prayerful support to the Perinovic family and all who are struggling to comprehend this tragic loss of life,” principal Adrian Glasby said.
“Claire was a kind, diligent, and much-loved student at St Christopher’s, and we were looking forward to welcoming Anna, with her huge smile, into prep to begin her school journey in just a couple of weeks’ time.”
Mr Glasby has provided parents with advice on how to share the tragic news and support their children through their grief as ongoing counselling is provided to families and staff.
Friends and neighbours of the family who live in the suburban street are also struggling to comprehend the tragedy.
Marie Groves, who lives around the corner, last saw her friend Katie Perinovic at her daughter’s birthday party at the end of November.
It was a warm spring day and the children, who had grown up living just a few hundred metres down the road from each other, played together all afternoon.
On Thursday night, Ms Groves struggled to tell her two young daughters that Ms Perinovic and her three children had died.
“That was hard. Especially to Jasmine, my youngest. She’s seven, she’s one of Claire’s friends,” she said.
Ms Groves said the neighbourhood was full of young families and all the children often played together in the street.
“Her kids were always playing in the street, but the past few weeks, I haven’t seen the family at all,” she said.
“We always caught up for play dates. She was over here or we went over to their place. Our daughters did dance classes together. Katie did everything for those children. She was very protective of them and always wanted what was best for them. It is just incomprehensible to me that the family is dead.”
Outside the family’s home, toys including a pink plastic teapot and yellow bucket were scattered in the front yard as investigators left the house holding brown bags of evidence on Friday afternoon. The blinds were drawn, but colourful children’s drawings could be seen stuck to the windows.
Police were alerted to the discovery of the bodies of the mother and her three children just after 12.30pm on Thursday after Mr Perinovic, 48, found them and called emergency services.
It was only a day earlier that his wife, Katie, arrived at the Schembris’ front door to drop off a bag full of ripe plums she picked from the garden.
It was not uncommon for the two families to exchange gifts. Ms Schembri had brought the children Christmas stockings filled with chocolates and lollies days before Christmas.
“We are just broken by what has happened,” she said. “They were the most beautiful kids.”
On Friday morning, Burgess Street was reopened by police, with detectives remaining at the scene throughout the day.
Strangers overcome by grief began to arrive at the house laying bunches of flowers outside the family’s brown brick home.
Warrick McGuire, from Essendon, brought his wife and young child to lay a small bouquet outside the house.
“We broke down crying when we saw it on the news,” he said.
Friends said Ms Perinovic (nee Blazevic), who worked as a physiotherapist in nearby Glenroy, had grown up in Tullamarine and had family living nearby.
They said Ms Perinovic was extremely proud of her job and only last year had taken on the role of mentoring young physiotherapists who were beginning their careers.
Neighbour John Constantino, who spoke to Ms Perinovic the night before she died, has not been able to stop thinking about their last conversation.
“I was watering the garden about 7.30pm and she walked past and she seemed happy and everything,” he said.
“She asked me what I was going to do tomorrow, I said, ‘I might mow the lawn’ and she said ‘Yeah, it’s not going to be a hot day’. Everything seemed so normal.”
He said described Ms Perinovic as a doting and caring mother and said her children loved to pat his dogs when he would walk them past their house.
A light rain fell on a makeshift memorial out the front of the house on Friday afternoon as another mourner left a handwritten note.
“You will all be sadly missed,” it read. “Our hearts are broken. Our kids loved playing with your beautiful kids always. We will alway remember you.”
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Melissa Cunningham is The Age’s health reporter.
David Estcourt is a court and general news reporter at The Age.