The toddler died a day after her dad was granted full custody by a court.
In a significant development, it has also been revealed that law enforcement came to the house one day prior, to effect the court ordered transfer of custody from her mother, but left without the girl when Arce refused to hand the child over.
Stephen Boyd, the girl’s father, had continued to call authorities the day of  her death, urging them to collect his daughter.
He was granted a court order after telling a judge that his ex had gone off her medication and was not capable of caring for their child.
The defense plans to argue that either that decision, or Arce discovering her daughter already dead, is what set off her psychotic episode.
Gabriella was covered with a sheet and surrounded by stuffed animals as well as notes written by her mother saying that she was with the angels, according to the Westchester County District Attorney.

Cynthia Arce, seen in court [photo], on Tuesday, is facing second-degree murder in the  death of her 2-year-old-daughter, as well as two counts each of Attempted Aggravated Murder, Attempted Aggravated Assault upon a Police Officer and Assault in the Second Degree for her attack on officers.

Police were called to the scene, however, not because of the toddler but rather Arce, whose mother Maria Solorzano called authorities after finding her daughter in a bathtub, according to court records.
All that is noted in the report is that Arce’s body was submerged in her water, except for her head, and there was note nearby that said she was ‘with her daughter.’
It was when police arrived on the scene that they found Gabriella and immediately got to work trying to revive the girl.
Solorzano told detectives that she had thought the girl was simply asleep.
Wrong victim: Officers arrived at the home where Arce and Gabriella lived after receiving a call that Arce was dying from her mother, who had found her submerged in a tub with a disturbing note.
The ‘dying’ woman exhibited almost ‘Super human strength’, officers had to shoot Arce when Tasers failed to subdue her demented attack as they responded to the emergency call made by her mom.

‘Arce had both her hands hidden behind her back and refused to comply with repeated police commands to show her hands,’ the DA’s office said in a release.
‘Arce then brought both hands from behind her back and above her shoulders revealing two large knives, one in each hand.  She charged at the officers, repeatedly slashing at two of them.’
The officers attempted to subdue her with Tasers, and when that failed she was shot by a third officer.
Arce was in the hospital recovering from those wounds for weeks, which is why her indictment on the murder charge was delayed until Tuesday.
She had previously been indicted on the charges stemming from her alleged attack on the officers from her hospital bed.
‘Police Officer Osvaldo Ramos sustained a large laceration to his left hand as he tried to protect himself and Police Officer Joseph Gaglione, who had fallen to the floor, sustained a wound to his foot as he was kicking at the defendant to block her attack,’ revealed the district attorney’s office back in May.
The next court hearing in the case is scheduled for October 2.