LAFAYETTE, Ind. (ABC News) — A couple who says that the little girl they adopted from overseas is actually an adult — who has threatened them. They’re now charged with neglect — for abandoning her.

“We were told by doctors, ‘This person is a sociopath. This person is a con artist. You are all in danger,’” recalled Michael Barnett, who, along with his now ex-wife, Kristine, thought they were adopting an adorable six year old girl, but this morning they claim the girl was actually an adult woman-who they believe was intent on killing them.

It’s a story just like the horror movie “Orphan” in which adoptive parents who say they are adopted a young girl…but who allegedly turns out to be much older.

Now Michael and Kristine could face jail time, accused by the State of Indiana of neglecting their adopted daughter, Natalia, leaving her behind after moving to Canada.

But according to the Barnetts, Natalia is not who she says. They claim she’s an adult, and that she was attempting to cause them harm.

“Natalia would do things, like place clear thumbtacks on the stairs face up so that when we would walk up the stairs we would be stepping on thumbtacks, to pain and injure ourselves,” Michael said.

“It wasn’t long after that that Kristine discovered evidence of a monthly menstrual cycle that Natalia, when confronted, stated that she did have one and she had been hiding it from us, and very, very shortly thereafter, Natalia ends up attempting to poison Kristine. She was pouring a bottle of Pine Sol into her coffee mug,” he said. “She had attempted to kill my wife for the second time this time by trying to pull her into an electric fence. We were asking police, please, after the second attempt, we would like to press charges please arrest her. And they kept pushing her into the hospital system instead of pressing charges.”

Natalia was allegedly 6 years old when the Barnett’s adopted her. She suffers from a rare form of dwarfism and Barnett says they very quickly noticed some suspicious behavior, including developmental changes consistent with adults.

He claims that doctors, testing, and even a court ruling led them to believe she was actually born in 1989.

”In 2012, based on evidence presented to the court, the Marion County Superior Court ruled that her birth year would be changed from 2003 to 1989 effectively changing her from eight to 22 years old,” Barnett said.

Still – there is confusion about Natalia’s age. Right now, she could be 16 – based on her original birth certificate – or 30, based on the revised certificate.

But officials, who believe she was a minor when the Barnett’s moved out of the country, arrested them both.

They face five years in prison if convicted.

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