A Victorian drug addict mother who killed another in a fight over $50 has ruined a family's life, a court has heard.
Alicia Schiller, 27, fatally stabbed ice-dealing mother-of-three Tyrelle Evertsen-Mostert in a substance-addled rage in the Geelong house they shared in 2014.
Schiller, a mother of one, started using drugs at 12, was a heroin addict by 21 and moved on to methylamphetamines in the months before the murder, her lawyer Scott Johns told a Supreme Court plea hearing on Friday.
Since going into custody, she has been taking part in all the drug counselling she can, Mr Johns said.
"Too late," the victim's mother, Johanna Evertsen-Mostert, muttered in the public gallery.
In a letter read out to the court, Ms Evertsen-Mostert said she was haunted by "the sight of my daughter lying on the floor...her eyes open and blank".
Tyrelle's death was "totally unnecessary" because "the money asked for was in her wallet," Ms Evertsen-Mostert said.
Her grandsons now must grow up without a mother, she said.
Mr Johns submitted his client did not intend to kill Tyrelle, making the murder less serious.
He said Schiller's life was "chaotic" and "unstable" in the months before the killing and that while in custody, she would have access to treatment programs.
"She went in with a weapon and utilised it from the start of the physical interaction, that's what makes it serious," crown prosecutor Mark Rochford submitted.
The prosecution also argued Schiller's six-page criminal record, including numerous assault and violence offences, and history of drug abuse meant there were "limited prospects of rehabilitation".
A Victorian Supreme Court jury in December found Schiller guilty of murder.
Schiller will be sentenced at a date to be fixed.