The boy, wearing a blue hooded sweatshirt and striped trackpants, stood expressionless in a Montreal courtroom as he was charged with manslaughter and illegal possession of a loaded, prohibited weapon.
While authorities did not lay murder charges in Monday's death of his 16-year-old sibling, they did not describe the shooting as a complete accident either.
"Obviously because he's charged with manslaughter, it's not an accident — the evidence doesn't show it's an accident," said Crown prosecutor Marie-Claude Bourassa, without revealing the suspected circumstances.
"We just study the evidence and charge as the evidence leads us, and in this case, the evidence leads us to these very serious charges."
Due to his young age, the boy faces a maximum sentence of three years in youth detention if convicted. He cannot receive an adult sentence.
His identity as well as his brother's cannot be revealed because they are minors.
The boy will remain in custody and is due back in court Friday for a bail hearing.
The prosecution, which offered few details about the case, is expected to provide more evidence to the defence from the ongoing investigation.
"We objected to his release today based on the gravity of the offences and because of the information that we have as of now," said Bourassa, who noted it was too early to say whether the Crown would ask Friday that he remain detained.
When asked by a reporter whether the boys' parents could face charges, Bourassa replied: "For now, we don't know. Like I said, it's an ongoing investigation and there are a lot of people to be met."
Police say the teenage victim was shot in the upper body with a handgun they said could have belonged to a family member.
The boy was arrested Monday evening after the shooting at the family's suburban Dorval home. He was questioned by investigators overnight, until 5:30 a.m.
The suspect was accompanied by a parent during the interrogation.
"It's a devastating situation," Bourassa said.
"He's 12 years old, so you can imagine how his parents and the family members would feel."
Less than 24 hours after his brother's death, the boy was straight-faced as he stood before Judge Elaine Demers in the defendant's box. His parents and a group of relatives looked on from the gallery.
His mother sat on the edge of her seat in the front row of the courtroom as another woman clutched her left arm. The mother lightly shook her head a few times during her son's brief appearance.
At one point during the proceeding, the mother stood up and started crossing the courtroom floor toward her son. She was stopped in her tracks by a defence lawyer who told her she was not permitted to do so.
Several of the boy's relatives looked exhausted and a couple of them slouched in their courtroom seats before his appearance began.
"This is a very sad event," police spokesman Simon Delorme said early Tuesday.
Delorme said police will not reveal the calibre of the gun, or whether it was registered, until investigators are finished meeting with potential witnesses.
The Crown, citing the investigation, also declined to discuss where the gun came from or where the suspect may have obtained it.
The boy, however, has had a run-in with police in the past. Bourassa told reporters he has an unrelated, pending court case for shoplifting.
Police said someone called 911 around 5:30 p.m. Monday to report the shooting in Dorval, west of the city. Paramedics tried to treat the seriously injured teenager, who was later declared dead at the hospital.
A spokeswoman for the local school board said counsellors were dispatched to the boys' schools to offer help for students and staff affected by the shooting.
A neighbour described the family in glowing terms. He shared his sadness at seeing one of the parents arrive at the house and leave in a "hysterical" state.
"That mom is one of the nicest ladies you probably have ever met in your life, so sweet and so kind and generous," the man said.
"I could never imagine what they're going through at this time of tragedy. I's very sad."
The neighbour had similar praise for the two boys, whom he said would sometimes offer to help him bring in the groceries.
"The boys are well brought-up, well-raised, very polite," he said.
"For their age, to be that polite was always a shock to me. I was always astonished about how polite they are."
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