An Indiana husband accused with his wifeof abandoning their adopted daughterin an apartment alone before fleeing to Canada has spoken out, alleging the daughter is a “sociopath” and a “con artist” who is actually an adult.

Appearing on ABC’sGood Morning America, Michael Barnett, 43, said that he and his wife, Kristine, 45, thought they were adopting an 8-year-old girl from Ukraine back in 2010.

The daughter has a form of dwarfism called spondyloepiphyseal, and two years after the adoption, the Barnetts had the daughter’s age changed to 22. Barnett toldGMAhe and his wife now think she may be as old as 33.

Barnett said doctors treating the daughter — identified only as Natalia — told them “this person is a sociopath. This person is a con artist. You are all in danger.”

According to Barnett, Natalia was bent on causing them harm.

Tippecanoe County Jail (2)

Kristine and Michael Barnett

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

Natalia is now staying with a different family in the United States,GMAreports.

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Michael and Kristine Barnett have both been charged with two counts of neglect of a dependent. They have pleaded not guilty to the charges.

It was unclear who Kristine’s lawyer is. An attorney for Michael did not respond to PEOPLE’s request for comment.

Kristine Barnett.YouTube

Kristine Barnett

WLFI reportedthat on Sept. 5, Kristine and Michael allegedly admitted to changing the Natalia’s legal age, but did not specify how they did so. They also allegedly told authorities that they rented out an apartment for Natalia but said they did not provide her with any other financial support other than paying the rent.

It is not known how long Natalia lived in the apartment before police got involved.

Kristine is a published author, who gained fame following the release of her bookThe Spark: A Mother’s Story of Nurturing, Genius, and Autismin 2013.

The book, which received rave reviews fromthe Washington PostandNewsday, is a memoir about Kristine’s life as a mother to her son Jacob, whose “extraordinary mind was almost lost to autism.”

source: people.com