Netflix’s docuseries about the Gilgo Beach murders mentioned Shannan Gilbert and her death often — but chose to omit how her mother was killed before Rex Huermann‘s arrest.
Gone Girls: The Long Island Serial Killer, which premiered Monday, March 31, introduced the Gilgo Beach serial killings through the lens of Mari Gilbert‘s search for the truth after her daughter Shannan went missing. Mari ultimately died before Huermann was arrested in connection to the murders.
“Some families aren’t here to see this justice. Both Megan Waterman’s mom, Lorraine Ela, and Shannan Gilbert’s mom, Mari Gilbert, passed away,” revealed a reporter interviewed for the Netflix special. “They fought so hard for this moment. I just wish they were here to see it.”
Meanwhile, journalist Robert Kolker, who is an expert in the Gilgo Beach case, added, “I believe Mari would still be campaigning to have Shannan’s death ruled a homicide, and she would not be convinced that Shannan’s death was disconnected from the others.”
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Shannan disappeared in 2010 after visiting a client in Long Island she met on Craigslist. The search for Shannan resulted in the discovery of four bodies — Waterman, Melissa Barthelemy, Amber Costello and Maureen Brainard-Barnes — which revealed the existence of a then-active serial killer. (More searches uncovered the remains of seven more people, including a toddler.)
Huermann was arrested in 2023 after the case went unsolved for more than a decade. He was charged in connection to Barthelemy, Costello, Waterman and Brainard-Barnes’ deaths and later with the deaths of Sandra Costilla and Jessica Taylor.
Shannan, however, was found dead in 2011. Police suspected that she got lost in the Gilgo Beach brush and died accidentally from either exposure or drowning. Mari wasn’t convinced and spent years advocating for authorities to include Shannan as one of Huermann’s victims. (Huermann has maintained his innocence in relation to every murder.)
“Shannan will be remembered for the girl who by her death exposed the truth and the killer,” Gilbert family attorney John Ray told People in 2024. “What Shannan’s case did is it forced the authorities to finally pursue the evidence that existed for the other girls. Shannan kept the pressure on all those years, even though she was dead.”
While Mari played a crucial role in keeping Shannan’s memory alive both in real life and in Netflix’s doc, her passing wasn’t addressed. In 2016, Mari was fatally stabbed 227 times before being bludgeoned to death with a fire extinguisher by her daughter Sarra Gilbert.
“So as a lot of you may know, my mother passed away yesterday. She was murdered by my sister, Sarra who was battling a mental illness for 2 1/2 years,” Sherre Gilbert wrote via Facebook in 2016. “My sister Stevie and I are incredibly devastated beyond words as our mother was the backbone of the family.”
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The lawyer, Ray, publicly stated that Sarra suffered both emotionally and mentally after her sister’s death. Sarra was subsequently sentenced to a prison term of 25 years to life.
“Mari’s life, transformed by the death of one daughter, had been ended by another,” Kolker wrote in his 2020 book about the Gilgo Beach murders. “She was not a perfect person and she was a confrontational person.”
Kolker continued: “But in her final years, she became the caregiver for another sick daughter of hers. And her tragic death was awful. But everyone I talked to who knew her well said that in her final years she had grown as a person and really found a way to keep on living despite such terrible loss.”
Gone Girls: The Long Island Serial Killer is currently streaming on Netflix.
