Rachelle Bond shot up heroin with her boyfriend Michael McCarthy after he beat her two-year-old daughter Bella Bond to death in her toddler bed, prosecutors said Monday.

Bond, the mother of a child known until recently as Baby Doe, was arraigned in court Monday along with her boyfriend — the child’s accused killer. McCarthy is charged with murder; Bond is charged with accessory after the fact.

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Prosecutors said McCarthy was certain that the child was posessed by some kind of demons and would regularly lock the child in a closet when she would get upset. The night Bella Bond was killed, McCarthy went into her bedroom and beat her because she was crying, prosecutors said. Rachelle Bond came in to find her daughter dead, prosecutors said.

Bond said that she witnessed Michael McCarthy punched Bella in the stomach until she stopped breathing.

Background: From Baby Doe to Bella Bond, a timeline

McCarthy said, "it was time for her to die" because she was possessed. Bond told investigators that he then grabbed her by the throat and told her that he'd kill her if she reported the killing. She said he put Bella's body and her blanket into a trash bag and put it in the kitchen refrigerator.

For weeks after, Bond said that McCarthy would regularly inject her with heroin to keep her sedated.

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Bond and McCarthy were arrested Friday, putting an end to an 83-day-long search for any information regarding the identity of a computer-generated image of a brown-eyed little girl.

Accoding to court documents, a friend of Bond's asked her about Bella on September 16. The friend said Bond told her that she would never be able to see her daughter again and that she was afraid of being an accomplice to a murder.  

The friend told investigators that they had witnessed McCarthy and Bond scream at the child, call her a "demon," and lock her in a closet. As images of Baby Doe circulated the television and social media sphere, the witness contacted McCarthy and Bond, accusing them of killing the little girl. 

According to prosecutors, McCarthy responded to the accusation by calling Bond a "cracked-out hooker," and saying that Bella was in DCF custody. After seeing the scetch, the witness and a family memeber called the police. 

Bella Bond's biological father, Joseph Amoroso, appeared at today's proceedings, as did Rachelle Bond's former friend Megan Fewtrell, 36, Fewtrell clutched a stuffed yellow duck she said Bella cherished. At one point, Fewtrell said she hoped Bond would "rot in hell."

Amoroso said outside the courtroom that he had never met Bella, and that he forgives Rachelle for the child's murder.

"If you look at Rachelle's neck, you'll see a track mark," Amoroso said. "McCarthy was dosing her with a gram to three grams of heroin to control her."

Bond is facing accessory to murder and improper disposal of a human body charges. McCarthy is facing first-degree murder and improper disposal of a body charges.

As McCarthy and Bond were lead out of the court, Amoroso shouted, "Michael McCarthy, you're done. You won't last a day."