Helen Jones (54) was convicted of the murder of her 55-year-old brother Paul at his home in Bandon Road in Cork city on September 4, 2019.
Her former partner Keith O’Hara, who blamed Helen for the killing, was also convicted of the murder.
The jury of four woman and six men sitting at Cork Central Criminal Court took three hours and 45 minutes to deliver their unanimous verdict for both co-accused.
The pair were also both convicted of trespassing at the property of Mr Jones to commit serious harm.
Both defendants will be sentenced tomorrow. Victim impact statements will be delivered by members of the Jones family.
The verdict followed a lengthy trial, which got under way on November 23.
Mr Justice Michael McGrath thanked the jurors for their "care and attention” to the case and informed them they were exempt from jury service for life.
Brendan Grehan SC, for Jones, asked if his client could stay in the holding cells during the victim impact sentence as she fears becoming physically ill. Mr Justice McGrath said he would consider the matter in the morning.
O’Hara and Jones were living together at Cahergal Avenue, Mayfield in Cork at the time of the offence. They were in a relationship but have since broken up.
They got a taxi to the home of Paul Jones on the evening of September 4, 2019 after Keith O’Hara told an acquaintance that the brother of his girlfriend “was going to pay for not handing over the house”.
The trial heard that the father of Helen and Paul Jones had left the family home in Cahergal Avenue to his two sons with the provision that Helen could live there until she married.
The jurors were told that there was a civil action with the late Paul Jones and his brother Liam on one side and their sister on the other.
It was settled on the basis that Ms Jones would settle her life interest in the house for €50,000. However, she continued to have feelings of bad blood in connection with the family home.
The prosecution evidence was that Jones hammered on the door of her brother’s house with a knife at around 9.30pm on September 4, 2019.
After several minutes, the two accused left the property and headed in the direction of McCurtain Villas where they were captured on CCTV.
Searches were carried out in the area and a discarded bill hook was found in the property of a garden in McCurtain Villas.
Keith O’Hara gave evidence in the case where he denied the murder of Mr Jones, instead claiming that Helen had killed her brother.
He said that they were “kind of engaged” at the time and that he didn’t call an ambulance for Mr Jones because he feared being “victim number two.”
He admitted hitting Mr Jones over the head with a bill hook, but he said that it was an act of self defence. He said that the bill hook was in the possession of Mr Jones and that he grabbed it from his hand.
“I pushed him and took it out of his hand and hit him on the head with it. I will be forever sorry about that,” he said.
"I had no idea that it was the bill hook that was in court. I just saw something black in his hand and grabbed it. I stumbled inside the door in to a load of blood a few feet inside the door. When I left (Paul Jones) was alive. His eyes were open and he said ‘I don’t know’.”
He denied stabbing Mr Jones.
Mr O'Hara said he had a tattoo with Helen's name inked on his neck 72 hours after the death of Mr Jones. However, he insisted he only did it to make an ex jealous.
In evidence, he denied the murder of Mr Jones and said his death could be attributed to Helen Jones.
O'Hara was asked by Mr Grehan if there was anything he would not say to "do her (Helen) down".
O'Hara answered: "Do her down? I am sitting here because of her. She killed her brother."
He said that Mr Grehan's client had "murdered her brother”.
"The dogs and the cat and the rat all know Helen killed her brother,” he added.
O'Hara gave evidence in which he claimed he didn’t see a knife in the hands of Ms Jones at the house in Bandon Road. He said she did straddle the victim and he thought she was punching him.
He insisted that he only realised afterwards that Helen had been stabbing her brother. He emphasised that it was his intention to get her away from the door of her brother's home in Bandon Road on the night in question.
He stressed he saw Mr Jones “swinging” for Helen and grabbed the bill hook from him in an act of self defence.
O'Hara stated that Mr Jones was a nice man and that not a day has passed where he hasn't felt sorry for the deceased
"Maybe in some other life the Jones family will forgive me for my part in what happened that night,” he said.
O'Hara admitted throwing a bill hook in the garden of a house in McCurtain Villas on the evening of September 4, 2019 but denied that he was trying to hide it.
“If I was trying to hide it I would have taken it and buried it,” he said.
Under cross examination by prosecuting barrister, Siobhan Lankford, O’Hara admitted lying to gardaí during his interviews in the aftermath of the murder.
“I am here to speak the truth. I was a coward. I was lying then,” he said.
The court heard that O’Hara told gardaí that bruises on his arm were caused by “rough sex”. When interviewed in connection with the murder, he said that neither he nor Jones left the house on the evening of September 4, 2019.
He claimed in his garda interviewed that he heard the news of the death of Mr Jones via media reports. He also emphasised to gardaí that he did not murder Mr Jones.
He also said in his garda statements that on the night of September 4, 2019 he and Helen watched
Coronation Street and other soaps.
He claimed they went to bed where they watched the Netflix prison drama
Orange is the New Black.
The trial also heard evidence from Chief State Pathologist Dr Linda Mulligan, who carried out a post-mortem on Mr Jones, who was living alone in Bandon Road at the time of his death.
His body was found in the hallway of the house three days after his death by a family member who had become concerned for his welfare having not heard from him.
Dr Mulligan noted a chop wound to the head and a scalp injury. She said Mr Jones received 25 stab wounds to his neck, upper arms, abdomen, chest, right armpit and back. The stab wounds ranged in size from 2cm to 12cm. Seven of the stab wounds were 10cm or more in depth.
Mr Jones also had abrasions to his body, bruising, incised wounds and extensive bruising under the skin of the skull. His right lung had collapsed and there was damage to the right kidney.
Dr Mulligan said blood loss would have been extreme and that the bleed to the brain was in itself potentially fatal. She told the court that Mr Jones also had defence type injuries to the hand.
Dr Mulligan stated the cause of death was a "chop wound to the head and multiple stab wounds."
Helen Jones declined to give defence evidence in the case.