A 15-year-old boy who police say fatally stabbed his younger brother in a fight over loud music has reached a deal with prosecutors and likely will be committed for up to 12 months in a juvenile offender program, a prosecutor said Tuesday.

William Gorzynski has been held in juvenile custody since the Oct. 26 killing at his Coral Springs home, about 45 miles north of Miami.

Prosecutors on Monday charged him as adult with manslaughter, but say they have reached a deal with his attorney for him to be sentenced as a juvenile.

"This is a very serious case," Broward County prosecutor Maria Schneider said. "He's almost 16 years old and it is this office's policy that cases this serious get filed in adult court."

According to police, Matthew Gorzynski, 14, was playing music on a computer while the two brothers were home alone. William was watching television nearby and complained the volume was too loud. The two yelled at each other, then got into a physical altercation. Police say William Gorzynski then went to the kitchen, grabbed a 7-inch knife and fatally stabbed his brother in the upper left chest.

Under the deal, Schneider said, Gorzynski will receive juvenile sanctions that include up to 12 months in a juvenile offender program and supervised release possibly up to his 19th birthday.

If he doesn't re-offend during that time, the charge will remain only on his juvenile record, Schneider said.

If Gorzynski does commit a new crime either in custody or during his supervised release, he could face the full sentence of the adult manslaughter charge, up to 15 years in prison.

"It gives me the ability to backtrack should he prove me wrong," Schneider said of the adult charge and the deal.

If he was charged as a juvenile and re-offended, he could only be brought back to juvenile court, she noted.

Gorzynski is set to be arraigned later this week, when the deal will be entered into the record. Gorzynski's attorney did not return messages from The Associated Press on Tuesday. Gorzynski's father, Thomas, declined to comment.