Kamiyah Mobley, the 18-year-old abducted as a newborn from a Florida hospital and raised by her alleged kidnapper in a South Carolina home, found out she was abducted about two years ago when she went to apply for a job, according to a friend.

“She was upset about it,” Arika Williams, who long believed she was Mobley’s half-sister, tells PEOPLE. “She even stayed home from school the next day.”

Mobley was only hours old on July 10, 1998, when authorities allege Gloria Williams posed as a health care worker and took her from a Jacksonville, Florida, hospital maternity ward. According to local reports, Mobley was briefly handed to Williams because her family believed she was a nurse, while hospital staff believed Williams was a relative.

Williams was arrested Friday at her home in Walterboro, South Carolina, where she was raising Mobley — who was called Alexis Kelli Manigo.

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Arika says Williams broke down and told Mobley the truth after the teen was hired at a local restaurant and was asked to provide a birth certificate and social security information.

“Lexy didn’t have that so she asked Miss Gloria for it and Miss Gloria kept brushing it off,” says Arika. “Lexy kept being hard on her mother, like ‘Momma, where is my stuff? I want to get this job.’ Then Miss Gloria just broke down and told her this is why right here, you can’t do this. I kidnapped you.”

Jacksonville Sheriff Mike Williams tells PEOPLE investigators are still trying to put the pieces together.

“We don’t know exactly what she knew,” he says about Mobley. “We know that obviously there was conversation about her maybe not being her daughter. Did she confess completely to her, or did she just give her pieces of it? We are not quite sure at this point.”

According to Arika, Gloria Williams allegedly told her daughter she had been pregnant but suffered a miscarriage.

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“Gloria was pregnant at the baby shower and had people there bringing homemade quilts saying Alexis’ name on it,” Arika says. “Alexis Kelli Manigo was going to be spoiled regardless but I guess she said she lost Alexis Kelli Manigo. She was going to find Alexis Kelli Manigo and went and got Kamiyah.”

Sheriff Williams says investigators haven’t yet determined what prompted the alleged kidnapping. “We are still working on that,” he says. “We don’t know the answer to that as to why she did it and we don’t know if she told her. We don’t know how much conversation they had: whether it was over one day or whether it was over multiple days or weeks. We are not sure about that as of yet.”

According to ABC News, Williams allegedly told her ex-boyfriend Charles Manigo that she gave birth to their daughter when he was away. Manigo said he and Williams continued to date until 2003, raising Mobley together and sharing custody after they split.

However, a Facebook post on a page that appears to be that of Mobley says Manigo “did nothing” as a father figure.

“YOU WERE NOTHING TO ME MY WHOLE LIFE,” she allegedly wrote. “I CAN COUNT ON MY FINGERS HOW MANY TIMES I’VE SPENT THE NIGHT AT YOUR HOUSE.”

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Arika says that after Mobley learned the truth she started looking up stories about the case and allegedly called her birth mother, Shanara Mobley.

“She said she heard her voice and she hung up,” she says.

Arika says Kamiyah eventually “just let it go.”

“Gloria is all she knows. That is Momma to her,” she adds. “That is who raised her to who she is now. And no matter what that will always be momma to her.”

Sheriff Williams says he is not surprised Mobley has been supportive of Gloria Williams after her arrest.

“For all accounts she was well taken care of,” he says. “She was raised a normal, healthy 18-year-old girl. It is a lot for anybody to process much less a young adult.”

Sheriff Williams says there are still plenty of unanswered questions including why Gloria Williams allegedly chose the hospital for the kidnapping.

“I don’t know why she picked that hospital,” he says. “Think about the timing of the fact that Kamiyah’s mother was a young mother at the time — so how did she know that or did she know that?

“Was she just lucky in finding a young, underage mother that she thought maybe did not have family support or something? You can really go crazy trying to fill in the blanks.”

Adds Sheriff Williams: “It is an incredible story. It leaves you with many more questions than answers. Policeman are notorious for believing they figure something out relatively quickly and reading people but this is one of those that the truth is stranger than fiction. It is incredible. You can’t make it up.”



