A five-year-old boy who went missing and was later found dead in a Massachusetts state park reportedly had fentanyl in his system and had been the victim of violence and neglect, according to prosecutors.
The body of Elijah Lewis was found on 23 October a week after his mother, Danielle Dauphinais, and her boyfriend Joseph Stapf, were arrested in New York City for witness tampering and child endangerment.
A friend told The Boston Globe that Ms Dauphinais had referred to her son as "the next Ted Bundy and Jeffrey Dahmer," saying she wanted "him gone."
The mother reportedly claimed in texts that Elijah would urinate on his bedding and clothes and play in his own faeces. She said she "couldn't trust" the five-year-old.
The boy's death has been ruled a homicide. His cause of death was ruled to have been a result of violence and neglect, including "facial and scalp injuries, acute fentanyl intoxication, malnourishment and pressure ulcers."
After Ms Dauphinais and her boyfriend were arrested, they were extradited to New Hampshire, where they pleaded guilty to the charges.
Watch: Elijah Lewis Autopsy - Violence, Neglect, Fentanyl Intoxication Listed For Cause Of Death
They have not been charged with the boy's death.
Elijah had only been living with mother for a a few months before he disappeared. He lived with his father before, and it is unclear why he was sent to live with his mother.
The aunt of one of Elijah's brothers, MJ Morrison, spoke with The Boston Globe about the developments.
"I am sick to my stomach," she said. "I didn't expect anything [like] this. I was hoping this was an accidental overdose and he got into something [and] they just panicked and didn't know what to do."
The New Hampshire Attorney General's office determined that the couple told others to lie about the boy's whereabouts.
Ericka Wolfe, a high school friend of Ms Dauphinais, received messages from the mother complaining about her son. It was in these messages that Ms Dauphinais compared her son to serial killers and suggested she wanted him "gone."
Ms Wolfe forgot about the exchange until she saw a news report months later stating that the boy was missing. She shared the Snapchat texts with a family member, who then forwarded the messages to the police.
According to Ms Wolfe, the police never questioned her about the messages.
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