Boolaroo stabbing: Detectives open up on family’s torment as teenage daughter is accused of repeatedly stabbing her baby sister to death at their home

Detectives have revealed how a young family has been shattered to its core after their teenage daughter was charged in the brutal death of her 10-year-old sister.

Emergency services were called to the house in the suburb of Boolaroo, about 150km north of Sydney, at 3.45pm on Monday after reports of a domestic incident.

When paramedics arrived, they reportedly found the younger girl with multiple stab wounds to her upper body.

They frantically tried to save her life, but her injuries were too severe and she died on the spot at the family home.

Her older sister, who cannot be named for legal reasons, was arrested and charged with the murder.

Outside Belmont Police Station on Tuesday, Detective Danny Doherty told reporters that the girls’ mother was experiencing unimaginable grief.

“There is a family at home still grieving and trying to come to terms with what happened to the 10-year-old family member and their loved one,” he said.

Forensic investigators spent more than 24 hours at the scene where a ten-year-old girl was allegedly murdered by her sister

‘My thoughts go out to a mother who lost her ten-year-old child… and now has another daughter, the other daughter [who is] probably responsible for the murder of the ten-year-old.

“It’s a terrible situation for her to be in that household.”

He said the two girls were the only children in the family.

Det Supt Doherty would not comment on whether mental health was an issue, saying the information he could provide was limited because the alleged killer was a minor.

The family was not known to police and investigators are still trying to understand how the situation developed.

“There is no evidence from the information we have to suggest why this has happened, this has come completely out of the blue,” said Detective Sergeant Doherty, commander of the homicide squad.

Forensic investigators scrutinized the crash scene for 24 hours, working all night Monday and all day Tuesday.

Homicide Commander and Chief Inspector Danny Doherty addresses the media during a press conference on Tuesday

Pictured: A forensic investigator with a bag of evidence in the house, Tuesday

Part of the street remained closed to the public while police officers carefully guarded the crime scene.

Neighbors were shocked by the alleged murder and told Daily Mail Australia the community was close-knit and family-oriented.

One woman said she was home at the time of the alleged incident and said she heard no noise coming from the home at all.

“We thought there were a lot of sirens in the area, but they turned them off when they got onto the street because there was no traffic,” she said.

Another neighbor said the situation was tragic because the mother “lost everything.”

“She’s lost her family, it’s a tragedy.”

The 17-year-old’s case was heard at Broadmeadow Children’s Court on Tuesday.

She appeared through her lawyer and did not apply for bail.

The case will return to court on June 24.

Emergency services were called to the house in the suburb of Boolaroo, about 150km north of Sydney, at 3.45pm on Monday after reports of a domestic incident

Detectives declared the house a crime scene and launched an urgent investigation into the girl’s death