Pieces of blood-stained carpet were cut out by crime scene cleaners after Simone Mottram was stabbed to death by then-19-year-old Bradley Craig Mottram at their Inverell home in October 2015.

"I cannot afford to have the carpet and floor fixed and cannot afford to sell the house to start afresh because of having to disclose the history," Mr Hawke said at Mottram's sentencing hearing on Thursday.

He said varnish had also been removed in the kitchen and it was a constant reminder of what happened.

Mottram, now 21, is scheduled to be sentenced in the NSW Supreme Court later this year after pleading guilty to his mother's murder.

According to the agreed facts, he hit Ms Mottram over the head with a bottle of bourbon and stabbed her in the chest, neck, upper abdomen and face after she said something that made him snap.

Ms Mottram's father, Leopold Purer, said he nearly collapsed and was in disbelief when police arrived at his doorstep to tell him his daughter was dead and his grandson had been arrested for murder.

His pain and sadness are now greater than ever and he's "tortured by intrusive thoughts" and "nightmarish images".

"It has been shocking to discover in myself a depth of anger so corrosive that it makes me capable of having violent thoughts of retribution against my grandson," he said in a victim impact statement read out in court.

"Once I would have thought such a thing impossible."

Ms Mottram's mother, Maureen O'Bryan, said she had difficulty envisaging her daughter over the age of two or three.

When she tries to visualise an older Simone she only sees images of her violent death.

The court heard Mottram had a dysfunctional upbringing and struggled in the lead-up to the killing with substance abuse and deteriorating mental health.

His lawyer, Richard Wilson, said Ms Mottram had struggled with the responsibilities of motherhood but at the time of her death she'd achieved a great deal of stability.

The agreed facts state her relationship with her de-facto partner, Mr Hawke, was mainly happy although there had been alleged incidents of domestic violence.

Mr Wilson said his client had gone to his mother because he needed her help and it was an awful and tragic irony that he lost control.

Mottram had, during his time in custody, come to terms with the enormity of what he'd done and accepted he needed to be punished.

However, crown prosecutor Kate Ratcliffe questioned whether his remorse was genuine.

Mottram is scheduled to be sentenced by Acting Justice Peter Hidden on June 14.

Australian Associated Press