The devastated father of the Blue Mountains boys killed in a suspected suicide attempt describes the harrowing moment he found their lifeless bodies

The devastated father of two young boys suspected of being murdered by their mother in a suicide attempt has described to police the devastating moment he found their lifeless bodies.

Retail manager Nick Smith rushed to his ex's home in the quiet village of Faulconbridge in the Blue Mountains west of Sydney on Tuesday afternoon after he was unable to reach his former partner Trish Smith.

Her two young sons, 11-year-old Russell and nine-year-old Ben, had not arrived at Our Lady of the Nativity elementary school in the nearby village of Lawson as expected that morning.

But nothing could prepare her father for the gruesome sight that greeted him when he arrived at their modest wood-panelled bungalow on quiet Chapman Parade just before 12.40pm.

Her two children were dead – they had apparently suffered stab wounds – while her 42-year-old mother lay bleeding from cuts to her wrists.

After calling 911, Mr Smith waited at the scene alongside his sons until police and emergency services arrived.

Ms Smith was flown by helicopter to Westmead Hospital under police guard and treated for self-inflicted injuries before being arrested.

While police searched the crime scene at the house, Mr Smith – who was not living with the family at the time of the tragedy – went to the nearby Springwood police station to assist the homicide squad with their investigation.

No charges have been filed in connection with the incident.

The former couple, who bought the house 14 years ago, were well-known and well-liked members of the close-knit community and regularly attended the local Christmas street festival.

Ms Smith worked for the state government's Greater Sydney Local Land Service, while her ex-husband is a supplies manager at Big W.

The crime scene has been cordoned off for more than 24 hours while detectives try to reconstruct the events that led to the tragedy.

Mr Smith's Mercedes-Benz station wagon remains parked outside the family's property, which is cordoned off with police tape.

On Wednesday morning, detectives were still clearing away bags of evidence while devastated residents walked their children past the house on their way to local schools, Springwood High and Springwood Public Schools, down the street.

A local who knew the family brought their son, who left a toy truck at the scene of the accident

While investigators were still examining the crime scene on Wednesday, residents laid down their guard in front of the house.

Flowers were also laid in front of the Catholic elementary school they attend, about 13 kilometers away.

The young brothers were popular students and appeared in dozens of Facebook posts showing them smiling and receiving awards.

They had been at school on Monday. The police are now investigating the reason for their absence on Tuesday, before the tragic events that later occurred in their house.

The Parramatta Diocese of Catholic Schools released a statement on behalf of the school saying everyone who knew the boys was deeply saddened by their loss.

Residents began paying their respects to the house on Wednesday while investigators were still examining the crime scene

“Our Catholic school community is devastated by the tragic deaths of Ben and Russell, two students at Our Lady of the Nativity Primary School in Lawson,” the statement said.

“Counseling and wellbeing support is available to students and staff at Our Lady of the Nativity today and will continue to be offered in the coming weeks.”

“We greatly appreciate the care and kindness of the entire Blues Mountains community during this difficult time.”

“As the police investigation is ongoing, we are unable to comment further at this time.”

Blue Mountains Commander John Nelson said local officers were being assisted by detectives from the State Crime Command's homicide squad.

It is understood that an investigation is underway into whether Ms Smith may have suffered a psychotic episode prior to the tragedy.

The boy's father (pictured with his family) found the bodies of his sons and his former partner

A blue tarpaulin hangs in front of the house where the boys were found

Forensic experts recover bags full of evidence from the house

Police continued to investigate the crime scene on Wednesday morning

When asked whether Ms Smith had had any mental health problems in the past, he confirmed that we knew the mother, “but only for minor matters, so it would not be appropriate to comment at this time.”

Many of the family's neighbours told Daily Mail Australia they were too shocked by the violence of the alleged murders to fully process the incident.

They were surprised on Tuesday afternoon by the sound of police sirens on their normally quiet street, just 450m from the area's famous Norman Lindsay Gallery.

Photos posted on social media show the family beaming with joy as they posed for photos with Santa Claus, enjoyed the family holiday and explored the wilderness around the Blue Mountains.

Just eight months ago, Google Streetview images showed the children's Christmas decorations hanging in the front yard of the family's home.

Ms Smith had also previously spoken out online about mental health while working during the state's coronavirus lockdown, writing: “Mental health is not just for those who have been diagnosed.”

Retired homicide detective Steve Ticehurst, who lives just around the corner from the young family, said they were well-loved members of the close-knit community.

“They seemed like a really happy family. They've lived here for years and you would never expect something like this to happen,” he told Daily Mail Australia.

“They all came together for the Christmas party on the local street and seemed like the perfect family.”

“The mother used to be known for taking afternoon walks around the neighborhood to get some exercise, and we would always chat.

“There was never any indication that anything was wrong. I couldn't say a bad word about her.”

Another neighbor, who wished to remain anonymous, said the entire community was shaken by the incident.

“You used to see them all the time walking their dogs on the street and out and about with their sons,” said the resident.

“They were lovely young boys.

“You would never think something like this could happen here – it’s a quiet community.”

Local residents said they had not seen Mr Smith “for a while” but he once went to local events with the children and their mother.

The family is pictured in happier times. Father Nick Smith is on the right

Blue Mountains Commander John Nelson said local officers were being assisted by detectives from the State Crime Command's homicide squad.

Neighbor Barbara Faith said she regularly saw the two brothers riding their bikes home from school.

“They were wearing their helmets and doing the right thing… I just thought they were nice kids,” Ms Faith told ABC.

She said there was a huge commotion shortly after noon when about 20 emergency vehicles raced down her street.

“It’s such a quiet neighborhood and quiet street that you don’t expect something like this,” she said.

“It's just so sad. I can't believe something like this can happen anywhere, let alone on my street.”

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