Cristian Fernandez lives in a 30-square-foot cell in the Duval County Jail in Jacksonville, The (Jacksonville) Florida Times-Union reported Tuesday.
Fernandez was indicted by a grand jury for the March 14 beating death of his 2-year-old half-brother, David Gallariago.
He is the youngest person in the city's history to be charged with first-degree murder, the Times-Union reported.
If found guilty, Fernandez faces a sentence of life in prison with no chance for parole, the Juvenile Justice Information Exchange at Kennesaw State University in Kennesaw, Ga., reported.
Fernandez is in isolation because his age and the high-profile nature of his case forces the jail to keep him away from other juveniles, jail chief Tara Wildes said.
Fernandez's lawyer, Assistant Public Defender Rob Mason, said he wants the boy to be sent back to the juvenile facility where he was held for several months since the toddler's slaying.
"He's done well there and developed a good relationship with his mental health counselor," he said.
The prosecutor, Assistant State Attorney Mark Caliel, said juveniles must be treated as adults when facing adult charges, adding that safety at the juvenile facility is an issue.
"If I were the parents of a kid charged with petty theft, I would be outraged if someone charged with first-degree murder were there right beside them," Caliel said.
Fernandez is scheduled for arraignment Wednesday.
In case you missed it in the spoiler, this charge has never before been levied against someone so young. It's hard to make an informed opinion based on the scanty details made public so far, but I find it pretty shocking. He's 12; he's allegedly suffered extreme child abuse (I read this in a different article); he needs therapy, extensive therapy, not having his life taken away.