PHOTO: Florida boy Derek Rosa is seen in the first mug shot as he is charged as an adult for ‘stabbing his mother to death as she slept next to her newborn daughter’ – before ‘taking photos of her dead body and posting them shared with friends

A 13-year-old Florida boy who allegedly stabbed and killed his mother while his 14-day-old sister lay next to her in a crib has had his mugshot released.

Derek Rosa, of Hialeah, Florida, is accused of brutally murdering his mother, Irena Garcia, 39, in her bedroom last Thursday.

When emergency services arrived on the scene, Garcia lay dead with multiple stab wounds to the neck, while her newborn daughter lay unharmed next to her.

Rosa appeared stoic in the mugshot, with deadpan eyes, after he was charged with first-degree murder.

The young teen will be tried as an adult and did not appear in court for his first hearing today. He is held at the Miami-Dade Corrections & Rehabilitation facility.

Miami-Dade State Attorney’s Office officials said a grand jury has formally indicted him.

Today, Rosa’s father and grandmother appeared on behalf of the youngster. Emotional pleas were made during the hearing, emphasizing support for the young boy.

‘It is very unfortunate that this tragedy has occurred’ said his father, ‘but this child is very modest, very peaceful and no one could imagine that this would ever happen.’

After today’s hearing, a judge ordered him held without bond and transferred to the Metro West Detention Center.

He will be held temporarily while a judge reviews the defense’s request to return him to juvenile detention.

Lt. Eddie Rodriguez, a spokesman for the Hialeah Police Department, told WPLG-TV that the honors student called 911 just after 11:30 p.m. to report that he had “just killed his mother.”

A copy of the reporting call was also released by the police a few days before the first hearing.

In the transcript, the dispatcher asks Rosa, “Why did you kill your mother?” but no response is registered.

Rosa told the dispatcher that he had taken photos of his deceased mother and sent them to friends.

He is heard saying: ‘I took pictures and I told my friends. Is that bad?’

Police have not yet confirmed any details have been released. He also told the dispatcher he was “very sad” and wanted to “shoot himself with a gun” he had.

Police believe the boy waited until his mother fell asleep and then stabbed her several times.

Rosa is an honor student at iMater Charter Middle/High School.

Lt. Rodriguez said it was “not what you would think or expect when you go into that house or see that crime scene.”

Footage from the scene showed the boy walking out of the apartment as he was being arrested by police.

A neighbor, Lazaro Rodriguez, said, “I was shocked, just shocked by the news. He was always with his mother, calm, helping her carry parcels or shopping bags. I’ve never seen anything abnormal with him. I don’t know what could have happened.’

Rodriguez told Local 10 News last week that the boy had no history of mental health issues and that police had not previously been to the family’s apartment.

He said: ‘Neighbors don’t know about any problems in the house. So this has stunned investigators and us.”

Rosa lived in the apartment with his mother, newborn sister and his stepfather, who works as a truck driver, all of whom he reportedly got along well with.

Rosa was alone in the apartment with his sister and their mother on Thursday evening. His stepfather was reportedly in Georgia at the time.

Other family members were seen arriving at the apartment after Rosa was taken into custody.

In a family photo shared by local news media just before Garcia gave birth, Rosa and his stepfather are seen in matching light pink polo shirts and khaki pants, lovingly cradling Garcia’s baby bump.

Officials said his sister is now with her grandmother.

The teen was taken to a juvenile detention facility and then moved to Jackson Memorial Hospital after threatening to harm himself.

Rosa will appear in court next week for an arraignment hearing.