Blue Mountains Trish Smith (pictured) has been charged with the alleged murder of her sons

Police believe the boys allegedly murdered by their mother may have been killed up to 17 hours before they were discovered, court documents have revealed.

Trish Smith, 42, appeared in court for the first time on Saturday after she was charged with the alleged murder of her sons, Ben and Russell Smith, aged 9 and 11, who were found dead in their Faulconbridge family home on Tuesday. 

Emergency services were called to the Chapman Parade home around midday, following a report for a concern for welfare of a woman and two children. 

Police will allege that the bodies of the two boys were found inside 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 murdered sometime between 7.30pm on Monday evening and 12.30pm on Tuesday afternoon.

Smith did not make an application for bail when she appeared before the Parramatta Bail Court on Saturday morning represented by solicitor Paul McGirr.

She appeared before the court via video-link from Amber Laurel Correctional Centre, appearing on screen wearing a hospital gown and with her arm in a cast. 

Blue Mountains Trish Smith (pictured) has been charged with the alleged murder of her sons

Blue Mountains Trish Smith (pictured) has been charged with the alleged murder of her sons

She sat motionless with her head down as she listened to proceedings.

‘Can year hear us?’ she was asked.

‘Yes,’ Smith replied. 

She only spoke briefly, saying ‘thank you’ as she was told her matter will be next mentioned in court later this year. 

Outside court, Mr McGirr said the investigation was still ongoing and described the incident as an ‘absolute tragedy’.

‘There’s a lot of people hurting,’ the solicitor said.

‘At this stage I can’t say anything more in relation to what’s going to happen with the matter until we get all the material.

‘There’s a lot of family members who are really hurting in respect of this – parents, grandparents and the like. We’d ask that you respect that privacy.’ 

Russell and Ben Smith, aged 9 and 11, were found inside the Faulconbridge home on Tuesday

Russell and Ben Smith, aged 9 and 11, were found inside the Faulconbridge home on Tuesday

Police are seen outside the Blue Mountains home on Tuesday

Police are seen outside the Blue Mountains home on Tuesday

Paramedics treated Smith at the scene on Tuesday before she was taken to Westmead Hospital under police guard in a critical but stable condition.

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 on Thursday, the father of the boys said: ‘The loss of our two beautiful boys has caused unimaginable pain and distress.

‘They were happy, funny, outgoing boys, and were very much loved by their family and friends.

‘Like other boys their age, they loved sports, soccer, the Penrith Panthers, fishing, books, music, spending time with their friends and Max their pup. 

‘We appreciate the kindness and compassion shown by the community.

‘We also ask the media respect our need for privacy at this time, and give us the time and space we need to grieve.’

Smith will next appear in court on November 8.