13-year-old who allegedly stabbed mother to death in front of new baby to be charged as an adult

A 13-year-old Florida boy accused of fatally stabbing his mother as she was sleeping has been charged as an adult with first-degree murder.

Derek Rosa, 13, allegedly killed his mother Oct. 12 in their Hialeah apartment in front of her newborn baby, authorities said. Rosa was charged with first-degree murder by a Miami-Dade grand jury, which places his case in the adult felony court system, NBC Miami reported.

Rosa's first court proceeding was at a bond hearing Friday, when he was ordered to be held on no bond and remanded to the Miami Dade Juvenile Detention Center, online court records show.

At the hearing, Rosa’s father and grandmother testified on his behalf hoping the judge would release him on house arrest.

Hialeah police said that the deadly incident unfolded around 11:30 p.m. Oct. 12 and that officers responded after they got a call from the teen saying he’d murdered his mother, NBC Miami reported. Officers found his mother, 39, dead in her bedroom next to a crib where a 14-day-old baby was found unharmed. 

Audio of the 911 call to police, obtained by NBC News, revealed that he took photos of his mother's body and sent them to a friend on social media.

In the audio, which was redacted, Rosa is heard asking dispatch to send police to his home but saying he does not know the address.

His voice is noticeably shaky in his responses. Dispatch is heard asking, “I need to know if your mom is breathing,” to which he responded, “Ma’am, she’s dead,” adding there’s “blood all over the floor.”

He said his newborn sister was sleeping in her crib. Asked whether he harmed her, he replied: “I did not touch her. I didn’t want to touch my sister.”

Rosa said his stepfather has two guns, one he took with him out of the house and one left in the home. The teen said he wanted to kill himself and loaded the gun but couldn’t and left it on the sofa. 

“Miss, I took pictures, and I told my friend about it. Is that bad?” the teen is heard saying at one point. 

He says that he doesn’t know this friend’s real name but that he’s a friend he played games with online.

“I didn’t delete the pictures off my phone, but I sent them to him, and I told him I was sorry and said goodbye to him," the boy said.

Dispatch asked him why he killed his mother, but his response was redacted. At one point, dispatch said, “You stabbed her neck? Where else did you stab her besides cutting her neck?” and his response once again was redacted.

Officials said that the baby is the teen’s half-sister and that the mother’s husband is the teen’s stepfather, who was out of state when the slaying occurred. 

In letters to the court, Rosa’s father described his son as a respectful honor roll student who was a good kid well loved by his friends. His father acknowledged that he did not know what led to the stabbing but said that as a military man, he had taught his son good values, NBC Miami reported.

Rosa’s arraignment is set for at 9 a.m. Tuesday. 

An attorney for Rosa said Sunday: "My client Derek has strong support from his entire family. It is important to remember that only two months ago Derek was a 12-year-old child. We have full faith in the criminal justice system and due process of law."

Rosa faces life in prison if convicted, as the U.S. Supreme Court has ruled that the death penalty is unconstitutional for juveniles.