12-Year-Old Charged with Murder of Cousin, 8, After Alleged Fight Over iPhone

"I consider this to be one of the most disturbing violent acts committed by either an adult or juvenile that my office has prosecuted," said the DA -- who hopes to try the suspect as an adult --after describing video footage of the incident in question.

An 8-year-old is dead and her 12-year-old cousin has been charged with her murder in Humboldt, Tennessee.

While the suspect hasn't been named, the victim's mother, Rayana Smith, identified the deceased to WREG as Demeria Hollingsworth ( pictured above ).

"She liked to read books, go swimming, play outside, ride her bike every day, play with the kids in the neighborhood, play with my friends' kids. My baby was sweet," she told the outlet of her late child.

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According to a press release from prosecutors , Hollingsworth died on Monday, July 15. Two days later, the District Attorney General's office say they learned of home security video, which was then reviewed by authorities.

"This video showed the 12-year-old female juvenile (who will turn 13 next week) use bedding to suffocate her 8-year-old cousin, while the victim was sleeping in the top bunk of bunk beds they shared," read a statement from Gibson District Attorney Frederick Agee. "After the suffocation, the juvenile cleaned up the victim and repositioned her body."

"I consider this to be one of the most disturbing violent acts committed by either an adult or juvenile that my office has prosecuted," Agee continued, while announcing the first-degree murder and tampering charges against the 12-year-old girl.

"Due to the horrendous nature of this crime," Agee's office also said they're petitioning the judge to prosecute the girl as an adult, "which allows for a lengthier sentence, whether that will be through incarceration or supervision with court-ordered conditions."

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The victim's mother told WREG that the two girls were staying with their grandmother for the summer and were arguing over an iPhone before the death.

"When they told me about that, I should have just gone to get my kid. But they were having fun for the summer and I didn’t think she would kill my baby," Smith said. "She did nothing to deserve for her life to be taken. She was only eight years old. She just turned eight in April."

"Last time I seen my baby, she was smiling, giving me kisses, telling me she will see me when it's time for her to come back home," said Smith, who reportedly told the outlet she hopes the suspect gets the maximum sentence possible.

"She never coming back home. She never coming back home."

A GoFundMe set up for Smith's family has already raised more than $16,5000 -- surpassing its $10,000 goal.

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