The sibling of the perpetrator revealed his mother and father "were unable to handle" of their child and he worried his younger sibling would murder a member of their relatives, a public inquiry has heard.
Axel Rudakubana, a teenager, killed three youngsters at a pop music-inspired dance workshop on 29 July 2024.
The hearing, sitting at Liverpool Town Hall, heard the sibling the older brother told a friend there was a possibility of his sibling "doing something that could kill."
The hearing was advised the brother messaged his contact over the Discord messaging app: "Confrontations are frightening because of the danger of a fatality."
The sibling stated his brother reminded him of the psychopathic killer in the movie the thriller.
Increasing Conflict
The hearing learned the brother was diagnosed with a medical condition at the twelve years old which resulted in him relying on a chair and his mother and father offering greater support.
Questioned by the inquiry counsel, attorney, if that affected their bond he stated: "There was tension that emerged."
He acknowledged his sibling seemed to dislike this development.
He testified the inquiry that after the household moved from their previous home to the seaside town his relative's behavior worsened and he would have "physical explosions."
The hearing learned Dion became "progressively concerned" of his sibling, who would physically assault him frequently.
He said: "I had to be cautious if I did speak to him because any disagreement could escalate into an altercation."
'Genuine concerns'
Dion revealed his brother became much more aggressive after he was dismissed from his school in Formby, Merseyside, in that period.
Dion departed for higher education in the following period and the two spoke less and less "due to unfamiliarity with having me around."
The inquiry was told about a message Dion wrote to a friend on Discord in which he mentioned his relative was annoyed by him speaking late at night because of the limited soundproofing in their house.
He additionally informed his contact there was a danger of "his committing an act that could kill."
He stated: "The fights are scary because of the threat of someone dying."
Mr Boyle asked: "You held real worries that your relative would fatally harm a person of your family?"
He responded: "Should situations worsen to that level."
Mr Boyle questioned how his mother and father dealt with the perpetrator's aggression.
"It didn't make sense to try and punish him," he said. "Moreover, there was a heavy risk in doing so.
"We said there was a widespread threat to well-being in casual discussion, if you try to confront him... it wouldn't be responded to well."
When questioned if his mother and father had lost control of his sibling, he agreed.
Inquired concerning his sibling reminding him of a persona from the film the Coen brothers film, the brother explained: "It was said that character's intended as a psychopath and that's why I employed that term there."
He revealed the previous encounter he had with his sibling was in the summer of 2023.
He stated that their family requested the attacker to bid farewell to him as he was departing to visit his associates and his relative tossed a container at him but the exit was secured before it struck.
The inquiry ongoing.
