The brother and sister bit her arms, kicked her and pulled her hair as they tried to save the infant's life; the 12-year-old broke free to unlock the door to allow Randy Montano — the baby's father and the older children's stepfather — to rush in to try and stop her, having heard the cries for help, official records show.
As he tried to pry Carmenate's hands from their daughter's throat, they fell to the floor, causing the baby to suffer a head injury, the report states.
Montano fled the apartment with the baby, after which the other children told police she then tried to strangle her son; he managed to wrest himself free and escape too.
While fleeing, he told investigators he then saw his mother dragging his sister back into the room by the hair; she told police her mother began squeezing and twisting her throat, telling them she "could no longer breathe, and thought she was going to die," Fox6 reported. Her mother eventually released her, and she too managed to flee.
According to both children, their mother believed she had successfully murdered their sister, telling officers they heard her say: "I just killed a six-month-old baby."
Montano told police this was the first time Carmenate ever did something like this, and that he believed she was suffering from post-partum depression. Their baby daughter, he said, was doing fine.
Carmenate faces two counts of attempted premeditated murder, as well as kidnapping and child abuse charges.
At her bond hearing on Monday, the judge described her nine-year-old girl as "a hero" for saving her sister's life. "The father had to blow air into the child's throat to save her life," the judge read.
Carmenate cried as the charges were read out, and the judge ordered her not to have any contact with any of her children.