Image source, Family photoImage caption, Nikita Dallison and Mellissa Arkwright have waived their right to anonymity to share what happen to them
Sisters Nikita Dallison and Mellissa Arkwright were just six and seven years old when they began to be abused by their half-brother Adrian Austin.
But while Nikita, 36, can remember the harrowing details vividly, Mellissa, 35, had no recollection of what happen to her as a little girl.
It was only when Nikita bravely reported the abuse to police in 2021 that Mellissa decided to have a type of talking therapy known as eye movement desensitisation and reprocessing (EMDR).
This involves listening to sounds, tapping, or flashing lights to remember a traumatic event.
"I needed therapy because my mental health had spiralled way out of control... but I never understood why," said Mellissa.
"It's horrific when you have it, because you feel every single sensation.
"You can feel the atmosphere in the room when you're having that therapy."
It unlocked a specific memory that would prove to be a crucial part of the evidence that brought their half-brother to justice.
Austin, now aged 45, was jailed for 17 years in July after being found guilty of six counts of sexual intercourse with a girl under 13, which would be classed as rape under current sexual offences legislation.
He was also convicted of four counts of indecent assault and one count of indecency of a child between 1997 and 2001.
"It's still upsetting thinking about that day [when he was found guilty] because we got justice for those little girls," said Mellissa.
"It was very surreal and I don't think I've ever cried like I did that day.
"It was like a whole weight had been lifted off my shoulders.
"I knew that it was over with. He can't hurt anyone anymore."
Image source, Family photoImage caption, Mellissa Arkwright and Nikita Dallison, pictured in 1996
Victims of sexual offences are granted automatic anonymity but Mellissa and Nikita have both waived their rights so they can share their story.
The abuse began after Austin moved into the family home in Manchester at the age of 10, having previously lived with his father.
"He was being inappropriate, asking to see our underwear and things like that and it escalated to touching," said Nikita, who can remember the "fear, confusion and dread" she felt as a little girl.
In a short space of time, he began to rape them, she said.
After years of silence, Nikita decided to report what happened to the police.
Her children were the same age that she was when she was abused and she could not fathom how someone could have been so cruel and twisted.
She also believed Mellissa's mental health had spiralled as she was reliving memories of the abuse, unaware that she could not recall what had happened.
Det Ch Insp Chris Preston, from Greater Manchester Police (GMP), said he first interviewed Nikita before sensitively approaching Mellissa, who was in the midst of a mental health crisis and had no memory of the abuse.
But, as the investigation continued, Mellissa shared the one memory she had retrieved from EMDR therapy.
"This kind of therapy is new to us and we had to do a bit of research to find out exactly what those letters even stand for more than anything," said Preston.
"The EMDR therapy was conducted by someone who became our expert witness in court.
"His evidence was so clear. It was incredible evidence as he really explained the EMDR therapy so clearly.
"Melissa was able to retrieve a very specific memory.
"She was able to describe the room, the slats on the bed, the gap between Adrian Austin's teeth when he was committing his awful crimes.
Image source, GMPImage caption, Adrian Austin has now been jailed for 17 years at Manchester Crown Court
During the investigation, it also came to light that Mellissa had given an interview about the abuse to police in 1997, but no further action was taken.
While little is known about the exact circumstances, police believe her parents reported the abuse to officers but took Austin's side.
It formed part of GMP's investigation in 2021 that their parents were aware of the abuse.
"'What happens in the family stays in the family' - that was our family slogan but not anymore," said Mellissa.
"They always used to say it all the time. But now, I'm not being silent anymore.
"So now it's like, I don't care anymore. I'm going to say my piece. I'm going to say what I need to say."
The video interview from 1997, which was uncovered on a VHS tape in a police storage room stacked with boxes from the floor to the ceiling, was also used as part of the evidence in the trial.
Austin later moved out of the home but continued to babysit Nikita and Mellissa in his flat in Manchester.
He was interviewed numerous times by police where he continued to deny his guilt, claiming the girls had never been to his flat.
But Nikita was able to outline the exact layout of the rooms, which matched housing records.
For Nikita, it was a massive sense of relief, when the jury returned a guilty verdict.
She said she also took comfort from knowing that her sister cannot remember everything that happened to them.
"We haven't, even now, spoken about it, as I'm very conscious that Melissa hasn't got these memories," said Nikita.
"I take a lot of comfort in that actually.
"I found it very weird when I first found out. I thought she was just hiding it and didn't want to say it.
"I know she knows some things now from court, which is sad, but I take a lot of comfort that she hasn't got them."
Image source, Family photoImage caption, Mellissa Arkwright and Nikita Dallison, pictured in 1994, before Austin moved in
Det Con Rebecca Lovekin said the sisters had shown "immeasurable courage, support and heart during these proceedings".
"Just reporting these offences was a huge step for them to take, and they have pursued it through to the end to see justice served," she said.
"We understand it was hard for both survivors that the initial investigation in 1997, regrettably, did not go as far as it should have.
"We have acknowledged this with both girls and apologised for the handling of the investigation at the time.
"Since then, we have progressed and the way we investigate sexual abuse, particularly historic sexual abuse has developed considerably, with a greater understanding of survivor experiences.
"The GMP of today has put Austin behind bars and secured justice for both girls."
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