Two Auckland sisters have waived their right to anonymity so they can name their stepfather who sexually abused them.

Photo: RNZ / Anusha Bradley

Celeste and Tiana Smith were abused for years by Ira Hayes Ricky Manamana, 43, who was last week sentenced at the Waitakere District Court to 16 years in jail with a minimum non-parole period of eight years.

At their request, Judge Kevin Glubb lifted the sisters' automatic name suppression.

The sisters said they wanted their name suppression lifted so they could encourage other people who have been abused to speak out.

Celeste Smith was 12 when Manamana first assaulted her in 2008. Over the next six years, it happened more than 100 times.

Now aged 20, she wants other sexual abuse survivors to hear her story.

"I felt embarrassed and ashamed of what had happened."

Celeste was abused by Manamana from March 2008 until March 2015. She did not tell anyone until September that year. Manamana was finally convicted of nine charges of sexual violation, rape and indecent assault in September 2016.

It took such a long time to tell someone about the abuse because it was hard to accuse a family member, someone who had brought her up and whom she had trusted, she said.

"He was meant to be taking care of me ... and he would make me feel like I was doing something wrong."

"One of the reasons I wanted the name suppression lifted is because I know it's not my fault, I didn't do anything wrong for this to happen to me and I just want other people to know that could be going through this, or went through this when they were younger, it's no way their fault."

Celeste's younger sister Tiana was 15 when Manamana started abusing her.

Now 19, Tiana hopes her story will also encourage other survivors to seek help.

"It can happen once but it still should not be brushed away," she said.

"For your own sanity, you should come out."

Speaking about the abuse and having their abusers' name in public gave them a sense of control they felt they lost during their childhood, the sisters said.

Their family and friends have rallied around them and the support they have received had been "amazing". They also had nothing but praise for the way their case was handled by police and the courts.

It was shocking to learn just how common sexual abuse is, Celeste said.

"It happens to one in three young women under 16, and it also happens to one in seven boys, and 90 percent of these attacks happen within their own home," she said.

This was something she only discovered once she had asked for help and said she wished she had known sooner, as it might have encouraged her to ask for help sooner.

"This really surprised me and made me want to speak out to help these people and say like 'Hey, it's not your fault'."

The girl's mother, who cannot be named for legal reasons, was devastated when she discovered the abuse and was proud of her daughters' decision to come forward.

"It takes a lot of courage for anybody to do."

She urged other sexual abuse survivors to not give up if the person they had chosen to speak to about their experiences did not believe them or help them.

"Don't give up, find somebody else to talk to."

Celeste and Tiana said the experience had brought them closer to their mother as a result.

"Speak up to someone. It will help you so much inside. You will feel so much different to the person you are today, you'll feel like nothing is holding you back," Celeste said.

"For me it was 'Why should I keep it a secret? Why shouldn't I tell people?' There is nothing to be ashamed of now," Tiana added.

During the sentencing, their mother and grandfather read out victim impact statements which described how Manamana had manipulated the family.

The sisters' grandfather told the court Manamana had been like a thief in the night who had come in through a window and stolen his mokopuna.

He said the shocking revelations of abuse had caused unspeakable grief, rivers of tears and sleepless nights.

Judge Glubb told the court because Manamana had shown no remorse for his behaviour, there could be no reduction in his sentence of 16 years.

Manamana will serve a minimum non-parole period of eight years.

A spokesperson for sex abuse prevention agency HELP, Kathryn McPhillips, said waiving the right to name suppression was a radical act on the part of the sisters.

Ms McPhillips said few offenders were convicted and, of those, many had name suppression.

"Although they may have faced a judicial consequence there was not necessarily a community consequence."

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