Vic mum taunts ex-partner over murder

A Victorian mother of six killed her ex-partner's mother and then phoned him to taunt him about what she had done.

Leah Marie Stensholt will spend at least 16 years in jail for the murder of Carol McDonald.

Stensholt had just argued with her former partner about their children when she drove to his mother's home in Moyston, in the state's west, to confront her late on May 5 last year.

When the 65-year-old woman would not let her in, Stensholt grabbed her around the throat, forced her into the kitchen and stabbed her in the throat with a knife she found in a drawer.

The 42-year-old returned to her nearby home where she rang her former partner Paul McDonald and told him what she had done.

"I've just killed your f****** mother and you're next," she said.

"Ring your mother. You won't get her, I've just killed her."

Stensholt, who had three children with Mr McDonald, was sentenced to a maximum of 20 years' jail at the Victorian Supreme Court, in Ballarat, on Monday.

Justice Elizabeth Curtain described the murder as cruel, callous, brutal and vindictive.

The court heard Stensholt had separated from Mr McDonald in 2008 after a volatile relationship, marked by his heavy drinking.

On the day she killed his mother, Mr McDonald had refused to return two of their children after a weekend with him and said he would be taking the matter to court.

Stensholt told police that when she was driving to Mrs McDonald's house she was really angry at Mr McDonald and his mother for all they had put her through over the years and that Mrs McDonald "started it years ago, making out that I was crazy".

When asked if Mrs McDonald had done anything to provoke her, she said: "no, just her little laugh".

Judge Curtain said in her sentencing she took into account Stensholt's immediate admission of guilt, her otherwise good character, her diagnosis of borderline personality disorder and her difficult early life.