The biopic mainly focuses on Mari’s hunt for answers about her daughter’s death, which may be connected to an even larger string of unsolved murders of female sex workers (believed to have been committed by the Long Island Serial Killer), but the real story is even more tragic.

What happened between Sarra Gilbert and her mom, Mari?

On July 23, 2016, Sarra murdered her mom by stabbing her 227 times and hitting her with a fire extinguisher, according to the Daily Freeman . “Sarra invited her mother over to her apartment, because she was hearing voices,” John Ray, the Gilbert family’s attorney, told PIX11 about what happened to Mari.

Before Sarra murdered Mari, she started displaying dangerous behavior.

In February 2016, Sarra was arrested in Ulster County and charged with endangering the welfare of a child and animal cruelty, per PIX11. A source told the local news station that she drowned a puppy in front of her 8-year-old son, took the young boy into the woods, and threatened to kill him.

Fast forward to May 2016, and Sarra was arrested again for criminal contempt. The same source told PIX11 that she’d violated an “order of protection” secured by her boyfriend.

Sarra was reportedly struggling with mental health issues before the murder.

“She started to hear voices and hallucinate a few years ago,” Ray also told PIX11. “She was in and out of psychiatric hospitals since 2014. I dont know why she was out.”

Her sister Stevie also testified at the murder trial that Sarra was driven by jealousy to kill her momand would have killed her too if she had the chance, according to the Daily Freeman .

Sarra Gilbert in the middle of her two sisters, standing behind her mom, Mari Gilbert.Sarra Gilbert in the middle of her two sisters, standing behind her mom, Mari Gilbert.

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“I believe her main focus was our mom, I do,” Stevie said. “If she could have got to me, yes, I believe she would have killed me too.”

Where is Sarra Gilbert now?

She is currently serving 25 years to life in state prisonthe maximum sentence allowed by law, according to the Daily Freeman . The publication reported that Ulster County Judge Donald Williams said, if he has anything to say about it, she will never walk free again.