When Michael and Christine Barnett adopted a six-year-old girl, an orphan from Ukraine, in 2010, they received the information that the girl suffered from a rare disorder that caused her to have dwarfism, says "Mirror".

However, not everything was as it seemed, and this bizarre case is now the subject of a documentary series "The Curious Case of Natalia Grace", which aired on Investment Discovery Television.

In the six-part series, Michael and his now-ex-wife Christine told their side of the story about Natalia Grace, the girl who lied to them about her age to harm them.

Michael Barnett claims he knows what tricks Natalia Grace was up to and that she was, in fact, an adult when she arrived at their home. Grace, on the other hand, denies these claims.

At the same time, Michael and Christine are acquitted of the (child) neglect charges they faced when they moved to Canada and left Grace alone.

The Burnetts claim that Grace was violent and tried to kill them after she moved into their home. The former spouses claim that Grace was 22 years old when they left her, and she claims that she was just a child. In 2012, they managed to change their adopted daughter's birth date from 2003 to 1989, meaning the eight-year-old girl suddenly became twenty-two.

In the first episode of the docu-series, Michael shared that he and his ex-wife noticed some suspicious things about Grace in the first few months of their life together. He said that on one occasion his wife was bathing Grace and noticed that the girl had "fully grown pubic hair". Then she invited him to the toilet to show him.

"I didn't know what to think. Is that possible? Is that even possible? Who is this person?” Michael said.

Despite everything, they continued to care for her and gave her "love and understanding".

Things got even weirder when Christine noticed that Grace had blood stains on her underwear, hinting that she had gotten her period – way earlier than she should have.

"I remember how he held himself at the time. Her hands were in front of her body and she said she got her period, but she hid it," Barnett said, adding that it was then that he began to doubt her age.

Meanwhile, Grace was adopted by Cynthia and Anton Manns and she now lives with them and their five biological children.