PICTURED Florida boy Derek Rosa appears in first mugshot as

PICTURED: Florida boy Derek Rosa appears in first mugshot as he is charged as an adult with “stabbing his mother to death while she slept next to her newborn daughter” – before “taking photos of her body.” and shared them with friends.”

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

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

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

Rosa appeared stoic in the mugshot, his eyes expressionless, after being beaten for first-degree murder.

The young teenager is being tried as an adult and did not appear for his first court hearing today. He is being held at the Miami-Dade Corrections and Rehabilitation Facility.

The mugshot of 13-year-old Derek Rosa, who allegedly stabbed and killed his mother while his 14-day-old baby sister lay in a crib next to her, has been released

The mugshot of 13-year-old Derek Rosa, who allegedly stabbed and killed his mother while his 14-day-old baby sister lay in a crib next to her, has been released

Rosa's mother, Irena Garcia, 39, had just given birth to his younger sister two weeks earlier.  The baby was found unharmed next to her body

Rosa’s mother, Irena Garcia, 39, had just given birth to his younger sister two weeks earlier. The baby was found unharmed next to her body

Rosa’s father and grandmother appeared in court on Friday on the teen’s behalf. Officials with the Miami-Dade District Attorney’s Office confirmed that a grand jury had formally indicted him.

The court heard emotional arguments emphasizing his support for the little boy, with his father arguing the incident was out of character.

“It’s very unfortunate that this tragedy happened,” his father said, “but this child is very humble, very peaceful and no one could have imagined that something like this would ever happen.”

Rosa was held without bail and transferred to the Metro West Detention Center.

He will remain there until the judge considers the defense’s request to return the 13-year-old to juvenile detention.

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

A few days before the first hearing, police also released a copy of the dispatch notice.

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

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

Rosa posed with his mother and stepfather in matching outfits for a maternity photo shoot

Rosa posed with his mother and stepfather in matching outfits for a maternity photo shoot

In the transcript, the dispatcher can be heard asking Rosa, “Why did you kill your mother?” However, no response was recorded.

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

He can be heard saying: “I took photos and told my friends about them. ‘Is that bad?’

Police have yet to confirm the existence of any images or messages to Rosa’s friends.

It was claimed he also said he was “very sad” and wanted to “shoot himself with a gun”.

Police believe the boy waited until his mother fell asleep and then stabbed her multiple 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 enter the house or see the crime scene.”

Footage from the crime scene showed the boy leaving the apartment as he was taken into police custody.

A neighbor, Lazaro Rodriguez, said: “I was shocked, just shocked at the news.”

“He was always with his mother, calm, he helped her carry packages or shopping bags.”

“I never saw anything unusual 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 police had never been to the family’s home before.

He said: ‘The neighbors don’t know about any problems in the house.’ That baffled the detectives and us.’

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

Rosa was arrested by police on October 12th.  A copy of the 911 call was released by police this week

Rosa was arrested by police on October 12th. A copy of the 911 call was released by police this week

The apartment block where Rosa lived with his family in Florida

The apartment block where Rosa lived with his family in Florida

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

After Rosa was taken into custody, other family members were seen arriving at the apartment.

A photo of the family shared by local news outlets shortly before Garcia’s birth shows Rosa and his stepfather in matching light pink polo shirts and khakis, lovingly cradling Garcia’s baby bump.

Officials said his little sister is now with her grandmother. Rosa faces a judge in an arraignment hearing next week.