Long Island Serial Killer: Amber Costello the Final Victim of the Gilgo Four

 The final victim of the initial four found along Gilgo Beach was 27-year-old Amber Costello. She disappeared in September 2010, just months before her remains were uncovered. Originally from North Carolina, Amber moved to Long Island as a teenager. She lived in the village of West Babylon with her sister Kimberly Overstreet and young daughter. Those close to Amber described her as friendly, generous, and devoted to her family. “She lit up a room,” said sister Kimberly. 

But Amber struggled with drug addiction and turned to escorting to earn money. While she had ups and downs with substance abuse, her family emphasized she was working to build a stable life for herself and her daughter. “She was trying to change,” Kimberly said. In September 2010, Amber arranged to meet a client at the Brewery gentlemen's club in Long Island. Security footage showed her entering the club on September 2, 2010, just after 1 a.m. She was never seen leaving. 

When Amber didn't come home, her sister reported her missing. With little information to go on, the disappearance drew little notice locally. The family faced months of uncertainty, dread, and false leads. At one point Kimberly thought she spotted Amber in Manhattan. “My hopes got up,” she said. “It ended up not being her.” Three months passed before the news of human remains being found at Gilgo Beach in December 2010. Kimberly waited in agony as police worked to identify the victims. She provided DNA samples, hoping for but fearing confirmation it was Amber.

 Tragically, test results verified Amber was among the murdered women. For Kimberly, the news meant “My worst nightmare came true.” She was crushed that Amber had fallen prey to such a terrible fate. Long Island investigators now linked Amber to three other vanished sex workers whose remains were discovered in the same remote stretch of beach. The women had all booked clients electronically and traveled to meet them along Ocean Parkway. Police believed a serial killer was exploiting vulnerable women in the underground sex trade.

As fear mounted locally, Amber's loved ones focused on memorializing the vivacious young woman the world had lost. At a candlelight vigil in 2011, friends emphasized Amber's warm nature. “She was very kind-hearted,” said Jessie Powers. The mystery surrounding her murder made grieving even harder. Seeking justice for Amber and the other victims became a mission. In May 2011, Kimberly Overstreet attended a Suffolk County legislative hearing arguing for more urgency in the Gilgo Beach investigation. Displaying photos of her slain sister, Kimberly criticized how long the cases had languished unsolved. “They were people who had lives taken away,” she implored.

 Along with families of other victims, Kimberly formed the advocacy group the Voices for the Equality of Women's Issues. They held rallies calling for protection and respect for sex workers. Kimberly and Amber's young daughter pleaded for anyone with information to come forward. In 2012, the FBI joined multi-jurisdictional efforts to solve the serial murders, pursuing leads across state lines. But the trail remained ice-cold. “Somebody has got to know who this person is,” said Kimberly, frustrated at the lack of progress or arrests.

Hoping to generate tips, police released sketches in 2013 of two unidentified suspects based on witness accounts. But no clear suspects ever emerged. Over the next several years, protests continued over the stagnant investigation. “How many more have to die before they capture him?" railed Lorraine Ela, mother of victim Megan Waterman. Ten years after Amber's death, Kimberly Overstreet was still tormented not knowing what had happened to her sister. “There’s a lot of sleepless nights,” she told Newsday. She understood the challenges given the passage of time. But resolution mattered to her and Amber’s now teenage daughter.

 Today, the mystery endures more than 12 years after Amber Costello's disappearance. But her spirit lives on in the hearts of loved ones determined to see justice someday. She is remembered as a woman who overcame struggles in life only to fall prey to unspeakable evil. While the Long Island serial killer has never been named, Amber's memory fuels the ongoing quest for answers. Her sister Kimberly says Amber "deserves to rest in peace.” Solving her murder remains critical in making that possible.