Image copyright CBS / The Oprah Winfrey Network

A Ukrainian orphan has denied posing as a child and then threatening to kill the US family who had adopted her.

Natalia Grace Barnett has denied claims by her former adoptive parents that she is a fully grown woman, close to 30.

"I'm 16," she said in her first interview.

"I was six years old when I came to the United States. I just know that a family came and visited me and after a while, they adopted me."

Natalia, who has a form of dwarfism, says she had been under the care of several foster families in America before she was adopted by Kristine and Michael Barnett, who lived in Florida, in 2010.

Kristine and Michael have said they were led to believe Natalia was six years old when they adopted her, but doubted her age, believing her to have been closer to 20 at the time.

The Barnetts have said they felt threatened by Natalia and eventually moved to Canada without her - but paid a year's rent on an apartment for her to live alone.

Kristine and Michael are currently facing charges of neglect and will stand trial in early 2020.

'I thought I'd found the right family'

"I actually thought I'd found the right family after bouncing around a lot of families," Natalia told US talk show host Dr Phil, about her adoption by the Barnetts.

"I thought I'd found the right family for me."

Natalia admitted a previous family had returned her to US social services when she injured another child.

"One of the boys, me and him were really close so we wrestled almost, but I landed on his arm wrong so the mum thought I was trying to break his arm," Natalia said.

In September this year, Kristine Barnett told Daily MailTV that Natalia threatened to stab her family in their sleep, tried to poison her coffee and tried to push her onto an electric fence.

Natalia denies all claims of trying to harm or kill the Barnetts or their children.

She told Dr Phil that poison claims were a misunderstanding while cleaning with Kristine, denies plans to stab them and says she would only have entered their bedroom at night if she had had a nightmare.

Image copyright CBS / The Oprah Winfrey Network Image caption Natalia appeared on the chat show with Cynthia Mans, who she currently lives with

Natalia also said that while she lived alone for a year as an eight-year-old, she lived on canned food left for her by the Barnetts.

She had been enrolled in an adult school and claims she was told by Kristine Barnett to tell others than she was 22 years old.

She appeared on the US chat show with Antwon and Cynthia Mans, the couple who she now lives with and who believe her to be a 16-year-old.

They say she has posed no harm to their family.

What claims were made against Natalia?

Natalia was first adopted by Kristine and Michael Barnett - who already had three sons - in 2010. They say they believed she was a six-year-old from Ukraine, with a form of dwarfism.

But the family have claimed that shortly after adopting Natalia, they became suspicious about her real age because of her behaviour and maturity.

In September this year, Kristine told DailyMailTV that Natalia spoke more like a teenager than a child, didn't want to play with toys and wanted to spend time with older girls.

She also says there were physical signs that she might be older than the family believed.

"I was giving her a bath and I noticed that she had full pubic hair. I was so shocked," she said.

"I had just been told she was a six year old and it was very apparent she wasn't.

'She had periods and adult teeth'

"Natalia was a woman. She had periods. She had adult teeth. She never grew a single inch, which would happen even with a child with dwarfism."

Natalia denied that she had periods while she was living with the Barnetts in her Dr Phil interview.

Later, Kristine and Michael claim, Natalia became a danger to their family.

Image copyright CBS / The Oprah Winfrey Network Image caption Natalia cried when she was asked if she was a 33-year-old scam artist on US TV

In 2012 the Barnetts filed a motion with the Marion County Superior Court in Florida to have the date on Natalia's birth certificate changed from 2003 to 1989.

Kristine claims bone tests proved that Natalia was 14 or older at the time of her adoption, and says that Natalia confessed to being older than she pretended to be during a long-term stay in a psychiatric unit - where she was placed in 2012 by the Barnetts.

But in 2013, Natalia was discharged from psychiatric care and the Barnetts decided they were no longer willing to look after someone they claim they believed was an adult.

They furnished and paid rent for an apartment in Lafayette, Indiana where Natalia lived alone for a year, until she told police she had been abandoned by her parents in 2014.

Kristine and Michael will appear in court next year

Kristine and Michael divorced in 2014, but were taken to court earlier in 2019 accused of neglect by abandoning a child in 2013.

A trial date has been set for 28 January 2020 and after speaking to several news sources this year, have been issued with a gag order - which stops them speaking to the media about the case or Natalia.

But wait, isn't this already the plot of a movie?

Yes it is, it's the plot of 2009 film Orphan - which is about a couple who adopt a child who turns out to be a dangerous woman from Russia with a condition that stunted her physical growth.

In the film, the woman posing as a child murders several people - including her adoptive father.

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