A sister of a man accused of murdering their father says her brother told the family he would rather bear the brunt of their father's violence than watch his family be hurt.
The woman has told a court how her father laid siege to her family and their home on the night he was stabbed to death.
Jurors at the High Court in Auckland have heard how the deceased attempted to kick down the door and damaged his daughter's property while violently threatening members of the family.
The Crown said the accused murdered his father. The son's lawyers said he was acting in self-defence.
The trial is shrouded in extensive suppression orders, which means RNZ cannot report the names of the witnesses, the accused, his dead father or exactly when or where the killing happened.
Through tears the woman told the court how her father turned up to her house angry three times to terrorise the family, after beating up her mother earlier in the day.
"I remember dad screaming, I remember his arm being inside the window and I had these Christmas lights and he was that angry he was ripping them and trying to rip open the window," she said.
She, her partner and daughter, her mother and two brothers and sister-in-law were all hiding in the house the next time he turned up.
"Dad was kicking the door."
"I remember him screaming 'you f****ing wait till I get this door down'," she said.
The woman said she was "really scared".
She said her increasingly irate father, who had a history of violence and methamphetamine use, started focusing his threats towards her brother.
The woman said her brother wanted to face their father then and there telling her that he would rather their father "beat the s*** out of me than touch any of you".
The family managed to stop her brother from going outside.
The woman said she was usually able to calm her father down when he was enraged but this time his anger was unshakeable and she threatened to call the police.
"In my head, it worked," she said.
"We watch his car leave; we thought f***, he's gone to calm down, this is part of the routine where he goes home and he calms down and he leaves us alone," she said.
"He never carries on, or comes back"
The woman turned off the lights, checked the locks and went to calm her young daughter down. She didn't realise her father had only parked her car down the driveway - out of sight. He quietly made his way back to the house.
"That's when I heard the ruckus on the verandah - I was still alert and jumpy."
She followed the noise and ran down the hallway out of the open ranch-slider and on to the deck.
The woman saw her mother on top of her father and, fearing for her mother's safety, she yanked her off him.
Her mother asked her to turn on the lights, which she did, and that's when she saw what had happened.
"That's when I saw dad and he was sitting in my brother's lap."
She said her brother was crying and cradling their father repeating the words 'I'm so sorry'.
"He looked at me and said 'I'm sorry, I don't know how many times I stabbed him'."
Her brother had used her blue-handled onion knife to stab their father.
When the police turned up she told them her brother acted in self-defence, she said.
The trial is due to continue for another two weeks.