Back in 2010 Michael Barnett and his wife Kristine adopted a six-year-old orphan from Ukraine - but their happy family was soon shaken upside down.
The couple believed that Natalia had a rare bone growth disorder when they adopted her, but in a new docuseries airing on Investigation Discovery - The Curious Case of Natalia Grace - the story becomes more sinister than you could ever imagine.
A six-part documentary begins tonight and will air across three consecutive nights as the adoptive parents put forward their claims that the orphan they adopted was not a child at all but an adult who abused them and even tried to kill her adoptive mother.
Natalia herself has denied all the claims against her and meanwhile, Michael and his now-ex-wife Kristine were just recently acquitted of neglect charges after abandoning her to live alone in an apartment while they moved to Canada.
In the explosive new docuseries, the Barnett family documents what they claim is Natalia's disturbing behaviour and touches upon the tell-tale signs she was older than originally thought.
Michael and Kristine split up in 2014, but claim Natalia was an adult posing to be a child, who even allegedly attempted murder.
Following a few of the tell-tale signs that she was older - such as "full pubic hair" at six years of age and menstruating soon after, as well as meeting a girl with the same condition as Natalia and realising she was a lot more developed - a number of other curious things happened.
In the new explosive documentary series, Michael claims that the young girl "threatened to stab" her new adopted siblings.
He also claims that she tried to "poison" Kristine, adding: "One night, I opened my eyes and Natalia is standing at the foot of the bed with a knife in her hand."
But Natalia denies the claims and in a 2019 interview with Dr Phil, Natalia was shown a clip of Ms Barnett claiming she had tried to spray bleach into her coffee while they were cleaning together.
Natalia then told Dr Phil: "It was Lemon Pledge for tables. We had missed a spot so what I did was I scooted the chair over so I could get there and I scooted her coffee back so I could grab the thing because it was in front of it."
And responding to the family's allegations that she was an adult, Natalia said in the interview: "It's not true. It's not true at all. I just want people to hear my side."
Elsewhere in the docuseries, it is claimed that Kristina left the young girl outside for a period of time, which led to a police officer being called.
The officer then chatted with Natalia, with her revealing that she was told her birthdate at the orphanage in Ukraine, with Michael claiming in the new series that the officer told them that he believed her Ukrainian birth certificate was "bogus".
Then in 2012 the family successfully petitioned court to legally change their adoptive daughter's birth year from 2003 to 1989, which in turn changed her age from eight to 22.
With their adopted daughter now legally 22 years of age, they moved her into an apartment and then moved to Canada.
Michael and his now ex-wife Kristine were charged in September 2019 with multiple counts of neglect, with him acquitted last fall.
And in March of this year, the charges against Kristina were dropped, according to WTHR.
Meanwhile, Natalia has found a new family and is living with her new adoptive parents Cynthia and Anton Mans and their five children.
The Curious Case of Natalia Grace will premiere across three consecutive nights on ID beginning Monday, May 29, airing nightly from 9-11 pm ET/PT.
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