During questioning by Crown solicitor Anna Pollett yesterday, their mother Donna Fane told the jury Anthony told her on February 12, 2020 he had killed Lasslett and Littlewood.
Donna Fane also said Anthony told her he was happy he had done the murders as he had believed his partner, Jessie Lee Booth, was having an affair with Lasslett. He had been tracking Booth's movements on her phone and her bank account transactions.
Anthony was "hyped up and excited", she said.
Police found Lasslett and Littlewood's bodies in a converted shed on Lasslett's rural property about 8.05pm on February 11 last year.
Booth's body was discovered at a Lynwood Place, Brookfield, address on February 14 when police went to do a welfare check after her family could not contact her.
The cause of death was from multiple crossbow bolt wounds to her head, the Crown said.
The jury earlier heard police believed Anthony Fane killed Booth on about February 9, 2020, with the crossbow and bolts he had bought about a month earlier.
Donna Fane said Anthony was acting paranoid and his behaviour was "very erratic" and "overexcited", and that he told her he couldn't believe how easy it was.
"I was in shock and disbelief. I was quite fearful for all of us and I did not want Anthony to come back to my home."
Donna Fane said she urged Anthony to give himself up to the police but he refused.
He came back to her house and refused to leave, she said.
He told her he was going to sit on the couch and wait for the police to burst through the door and arrest him, she said.
"I was scared and really worried for all of us. Anthony needed to be stopped," she said.
"I was scared about what was going to happen as Anthony was acting erratically and very hyped up and told me he wanted to go out in a blaze of glory."
Anthony Fane was shot dead in Tauranga on February 13 last year.
Donna Fane told the jury Samuel and Anthony had visited her on February 11, the day of the alleged murders.
Samuel Fane told her he had come to support his older brother, she said.
Donna Fane said the two men and another brother Jesse spent some time on the back deck talking before Samuel and Anthony Fane left in a Blue Ford Territory belonging to Samuel's partner Sarah Lee Tarei.
Tarei, 25, is also on trial defending a charge of being an accessory to the alleged murders by helping him to evade arrest.
Donna Fane said she and Jesse were "shocked" when they saw a television news report about the alleged murders.
Samuel Fane called her the next day to say he and Tarei were heading to the South Island and needed "as much money as possible" for their road trip.
She did not ask him about his alleged involvement.
During another visit to her home Anthony Fane had also started "raving" about what he was going to do next to her, she said.
"He told me it wasn't over and he was going to go out in a blaze of glory. I told him to give himself up but he wasn't prepared to do that."
Anthony Fane left in his car, saying he had to "go to work" and that was the last time she saw or heard from her son.
Donna Fane said she called the police Crimestoppers line.
Later that day Tarei texted, her insisting she and Samuel did not know anything about what was going on and she urged them to come back home, she said.
"I talked to them about what they were going to do when it all unravels," she said.
Donna Fane also said Samuel had called her after seeing a news report about a person being shot and killed in Bethlehem, Tauranga, on February 13.
"My son Jesse and I both knew it had to be Anthony. We saw a picture of his car."
Samuel Fane was arrested the next day in Christchurch and the Crown says police found a shotgun in a bag in the room he and Tarei were sharing.
The trial presided over by Justice Gerard van Bohemen continues today, with Jesse Fane in the witness box.
