Over the last day or so, the story of Cyntoia Brown has swept across the internet.

You may have seen an emotional plea from Rihanna's Instagram or Kim Kardashian's Twitter alongside the hashtag #FreeCyntoiaBrown.

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Rihanna has posted multiple times to her Instagram, interrupting her feed of seemingly endless magazine covers, whilst KKW said she has called her lawyer to see what could be done.

But who is Cyntoia Brown, and why is everyone rallying behind her at the moment?

Now 29-years-old, Brown was sent to jail over 10 years ago in 2004 for killing a 43 year-old estate agent named Johnny Allen, who paid her for sex when she was 16.

In her 2004 trial, Brown told the jury that she was afraid of Allen - he had taken her back to his house full of guns when she was a sex worker - and that's why she shot him. But prosecutors claimed that she in fact killed him to steal from him, since she left the scene with some of his guns, as well as his trousers that included his wallet. The jury sided with the prosecution, and sentenced Brown to life in prison.

The young offender was the subject of a 2011 documentary by Dan Birman called, Me Facing Life: Cyntoia's Story, which renewed the public's interest in the case. The hour-long film, which is available on YouTube, charts the nuances of the case.

The film features heartbreaking interviews with a young Brown, as she alleges that at the time of the murder she was a sex trafficking victim and at the mercy of a 24 year-old pimp named 'Cut-throat'.

He was sexually, physically and mentally abusive to the then 16 year-old runaway. Brown says of her time with him, 'He would explain to me that some people were born whores, and that I was one, and I was a slut, and nobody'd want me but him, and the best thing I could do was just learn to be a good whore.'

She also details a life of abuse, with her mother and grandmother being survivors of rape and her adopted father being physically abusive.

A clinical and forensic psychiatrist also said that her alcohol-related neurodevelopment disorder (a type of foetal alcohol syndrome disorder that is a 'severe mental disease and defect') could explain her erratic behaviour.

Due to laws in Nashville from 2006, Brown, who has already served 13 years behind bars, is not eligible for parole until she has served 51 years, when she would be 67.

Laws have since changed, partly due to the 2011 documentary, which now state that people 18 or younger cannot be charged with prostitution.

During her time in prison, Brown has graduated from Lipscomb University with an Associates degree and has been working as an unpaid consultant for the Juvenile Justice System.

The hashtag #FreeCyntoiaBrown has now been trending on Twitter and public interest is mounting.

From: ELLE UK