Two teenagers from Florida will spend their lives in prison for the tragic murder of a 12-year-old girl, who was fatally shot while sitting on a couch, as a result of a dispute with her brother.

Matthew Rice, now 18, received a life sentence on Thursday for the 2023 killing of Mariah Smith in Lake City, according to a report by local ABC affiliate WCJB. Last month, a jury found Rice guilty of second-degree murder and two counts of attempted second-degree murder.

Previously, 17-year-old Jayden Burch was also sentenced to life imprisonment following his conviction on the same charges in August. A third suspect, Jatarious Rashad Fluellen, is still awaiting his trial.

Prosecutors indicated that Rice’s DNA was discovered on one of the firearms used in the crime. Despite numerous interventions—around 40 attempts—by school officials to correct Rice’s behavior, these efforts proved ineffective, according to WCJB.

The prosecution described Burch as the mastermind behind the incident.

“Without Jayden Burch, this homicide would not have occurred,” assistant state attorney Sean Crisafulli stated during the October 13 sentencing. “It was from Jayden Burch’s residence that these events were set in motion, and it was his conflict with Mariah’s brother that initiated this tragedy.”

Burch expressed no remorse. Instead, he was prideful, Crisafulli said.

“Within an hour of the homicide, he is bragging on Instagram to a girl about how he did this to [Mariah],” the prosecutor stated. “And then taking further actions to then cover it up, saying that he deleted the message, et cetera, not knowing that we could still retrieve them.”

Despite the evidence against him, Burch remained defiant.

“Honestly, did not take that young woman away from her family,” he said. “I know the things that y’all heard and seen make me look guilty. I honestly not do that. I know y’all want justice for [Mariah]. But y’all got the wrong person; I’m innocent.”

As Law&Crime previously reported, Lake City police responded shortly after 9 p.m. Aug. 24, 2023, to a home on NW Long Street to a report of a person shot. When they arrived, they found Mariah suffering from a gunshot wound to her head. First responders pronounced her dead at the scene. Investigators found 25 shell casings and a laser sight outside the home, a probable cause arrest affidavit said.

Over the ensuing days, weeks and months, detectives uncovered evidence the shooting originated from a fight between Mariah’s older brother and the suspects. Cops said Burch supplied the guns to the co-defendants and they walked to the home where they opened fire before running away.

Fluellen, who was 14 at the time, was the first suspect to be arrested. Burch, then 15, was taken into custody in October 2023. A grand jury indicted Rice in February 2024.

A key piece of evidence was an Instagram conversation involving Burch, according to a courtroom report from WCJB. He mentioned the shooting to someone which reportedly included a smiling emoji. When the person asked if Burch was aware of the shooting, he responded “I know, I did it.”

Cops also found Rice’s DNA on the laser sight. Jurors deliberated for less than an hour to convict him, per WCJB.

After the shooting, Lake City officials renamed the street on which she was killed Mariah Reginae Smith Forever 12 Memorial Street.

“This is history,” Mariah’s mother Todneisha Filer said at the dedication ceremony, according to local NBC affiliate WTLV. “This is the first time in history Lake City has ever done anything like this. No other family should have to go through what I’m going through and I’m praying that we can stop the gun violence.”