Court documents show police believe the boys were killed by their mother 17 hours before they were discovered.
Trish Smith, 42, appeared in court for the first time on Saturday after being charged with the alleged murder of her sons Ben and Russell Smith, aged nine and 11, who were found dead at their Faulconbridge home on Tuesday.
Emergency services were called to the Chapman Parade home around midday after reports of concerns for the welfare of a woman and two children.
Police allege the bodies of the two boys were found in the home by their father. Smith was also found with multiple stab wounds.
She was arrested on Tuesday and charged with two counts of murder on Friday.
According to court documents, police allege both boys were killed sometime between 7:30 p.m. Monday night and 12:30 p.m. Tuesday afternoon.
Smith had not made an application for bail when she appeared in Parramatta Bail Court on Saturday morning, represented by lawyer Paul McGirr.
She appeared in court via video link from the Amber Laurel Correctional Centre, appearing on screen in a hospital gown and her arm in a cast.
Blue Mountains Trish Smith (pictured) has been charged with the alleged murder of her sons
She sat motionless with her head bowed, listening to what was being said.
“Can the year hear us?” she was asked.
“Yes,” Smith replied.
She spoke only briefly, saying “thank you” when told her case would return to court later this year.
Outside court, Mr McGirr said the investigation was ongoing and described the incident as an “absolute tragedy”.
“There are a lot of people in pain,” the lawyer said.
‘I can’t say anything at this point about what’s going to happen with the case until we have all the material.
“There are many family members who are really hurting by this – parents, grandparents and the like. We ask that you respect that privacy.”
Russell and Ben Smith, aged 9 and 11, were found in their Faulconbridge home on Tuesday
Police are seen outside the home in the Blue Mountains on Tuesday
On Tuesday, Smith was treated at the scene by paramedics before being taken to Westmead Hospital under police guard. Her condition was critical but stable.
After being released from hospital on Friday, Smith was taken to Parramatta Police Station and charged with two counts of murder.
In a statement released Thursday, the boys’ father said: “The loss of our two beautiful boys has caused unimaginable pain and suffering.
‘They were happy, funny, outgoing boys and they were very much loved by their family and friends.
‘Like other boys their age, they enjoyed sports, football, the Penrith Panthers, fishing, books, music, spending time with their friends and Max, their dog.
We appreciate the kindness and compassion of the community.
“We also ask the media to respect our need for privacy during this time and to give us the time and space we need to grieve.”
Smith is due in court on November 8.