A Perth mother-of-five charged with murdering her husband and attempting to murder two of her children claims he physically and mentally abused her for years, and repeatedly threatened to kill them all.
Cara Lee Hall, 38, killed her 33-year-old husband Glenn Hall in December 2015 by stabbing him at least 16 times in the chest, neck, head and back in an early morning attack at their Leda home that began when he was asleep.
Their eldest son, 11, and youngest son, aged four, suffered knife wounds.
Prosecutor Louise O'Connor told Hall's WA Supreme Court trial on Thursday that there had been some previous violence between the couple but neither they nor the children had been seriously injured.
Neighbour Donna Moreschi-Andrews, who wept before giving her evidence, told the court the pair had a volatile relationship.
"They were very abusive towards each other, both physically and verbally" she said.
Ms Moreschi-Andrews said she heard a lot of yelling and screaming coming from the property, and once saw the victim smashing in the front windows.
She also heard him banging on the door and shouting to be let back in, but the accused would swear and tell him to go away.
The neighbour said she witnessed the couple hit each other in the front yard of the house on "quite a few occasions".
And if she heard the children crying or yelling out, she would call police, who attended 90 per cent of the time.
Ms Moreschi-Andrews said Hall had come to her house in an agitated state the day before the killing and called half an hour later to say: "I'm really sorry. I've been off my meds and looping out".
The court heard that when Hall called triple-zero minutes after stabbing her husband, she told the operator he was going to both kill their sons and sell them into the sex trade.
"I just killed my husband. He was trying to kill my kids," she said.
The court also heard she reported hearing a voice in her head before the attack that said: "One, two, three, go."
Defence counsel Mara Barone said there was no dispute her mentally-ill client inflicted the fatal injuries "but she did so in defence of herself and her children".
Ms Barone said Hall's actions were violent but necessary after years of physical and mental abuse, and repeated threats to kill them all.
"Even people with mental health issues need to defend themselves," she said.
The trial continues.
AAP