Natalia Grace was welcomed into Michael and Kristine Barnett's family 13 years ago when they adopted the six-year-old orphan from Ukraine.
The adoptive parents were initially overjoyed at welcoming the youngster into their family home in Indiana, but their world was soon shaken upside down.
Michael and Kristine started to doubt Natalia's age and claimed the youngster was actually an adult at the time of the adoption, even going as far as getting her age legally changed by 14 years.
They also said she threatened to kill them and their family, claims which Natalia continues to deny.
Now, her biological mother has spoken out about the claims as she insisted Natalia was a child when she was put up for adoption.
In a new Investigation Discovery docuseries, The Curious Case of Natalia Grace, Anna Gava recalled having a "difficult" birth with Natalia as she opened up about why she gave her child up for adoption.
"When I regained consciousness, after anesthesia, the next day the doctor came and said there is no sense to take her home.
"They said that she won't be able to walk at all and she will be of very short stature," she revealed via a translator.
Anna continued: "I didn't initially want to leave her but the doctors said there is nothing you could do for her. 'You are young,' they said. 'You are 24 years old. Don't ruin your life, you will have other children'."
Natalia's biological mother started to tear up as she spoke before admitting she had been thinking about Natalia "all those years".
Michael and his now-ex-wife Kristine were recently acquitted of neglect charges after abandoning Natalia to live alone in an apartment while they moved to Canada.
Addressing Natalia's life in America, Anna said: "When I found out what happened, that she was abandoned at the age of 13 alone in an apartment, I was simply shocked, obviously."
The interview then cut out, due to rolling blackouts in the area amid the war in Ukraine.
Michael reacted to Anna's claims, pointing out how her information has never been "validated in a court of law".
"Regarding the woman in the Ukraine that is supposedly her mom, I don't know the truth about anything. I don't know," he said.
"I have never met her, I've never been to the Ukraine, I didn't conduct any tests, I've done none of these things. Has this information been validated in a court of law? No.
"I have some test submitted by a prosecutor who has a reason to want to win their case."
Natalia has a rare form of Dwarfism called Spondyloepiphyseal Dysplasia Congenita, and has previously denied claims she abused her adoptive family and was an adult at the time of adoption.
Responding to the family's allegations that she was an adult, Natalia spoke to Dr Phil in an interview a couple of years ago when she said: "It's not true. It's not true at all. I just want people to hear my side."
Michael Barnett and his now ex-wife Kristine Barnett 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.
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