BARRE, Vt. (AP) — A Vermont woman facing life in prison without parole for killing a state social worker and three relatives left a screaming message threatening to kill one of her victims just hours before the shootings were carried out, the daughter of one of the victims testified Monday.

Tiffany Herring-Flint testified she heard her cousin, defendant Jody Herring, leaving an expletive-laced message on an answering machine telling Herring-Flint's mother and aunt they should stop calling the state Department for Children and Families. Police say Herring believed her relatives had played a role in her losing custody of her 9-year-old daughter.

"You might want to stop ... calling DCF or I'm going to come there and shoot your brains out," Herring-Flint said she heard Herring say on the answering machine in the house where Herring-Flint's mother, Rhonda Herring, aunt, Regina Herring, and grandmother, Julie Falzarano died hours later.

Vermont DCF social worker Lara Sobel was shot and killed as she left work in Barre on Aug. 7, 2015. Police later determined Herring had killed her relatives before she killed Sobel, although the three bodies were not discovered until the next day when Herring-Flint went to the house in the Berlin, Vermont, to check on her mother and the others.

Court documents say Jody Herring was seeking revenge against those she believed responsible for her losing her daughter.

Herring-Flint's testimony came on the first day of what is scheduled to be a five-day sentencing hearing for Jody Herring. Herring pleaded guilty in July to first-degree murder in the shooting death of Sobel and three counts of second-degree murder for the deaths of her relatives.

The plea deal calls for a sentence of 20 years to life in prison on the second-degree murder convictions. It will be up to Superior Court Judge John Pacht to determine if Herring is sentenced to life without parole on the first-degree murder conviction.

Witness Karlyn Sizemore testified she walked past Herring immediately before the shooting took place, she heard two shots and then saw her restrained by people in the area until police arrived.

"She was jumping around the parking lot, screaming, (waving) the rifle around. 'They didn't listen to me. It was my 9-year-old daughter. They got what they deserved,'" Sizemore testified she heard Herring say.

The first witnesses called by defense attorney David Sleigh were two of Jody Herring's aunts. They testified they grew up in a family of 16 children and were both regularly sexually abused by their father and subjected to physical and emotional abuse.

Sleigh also said Herring changed after her father died when she was 5 years old of what was ruled a suicide.

In a court filing last week, Sleigh wrote that Herring had been going through a mental health crisis earlier that year and was released early from a 90-day involuntary commitment. She still would have been in the hospital on the days of the shootings had she not been released early, Sleigh wrote.