Frustration grows seven months on as no arrests made following brutal murder of 18yo Ariki Rigby

Warning: Some of the details in this story are distressing. 

Seven months after 18-year-old Ariki Rigby was brutally murdered in Hawke's Bay, no one has been arrested. 

Her sister Anahera is growing frustrated, saying she's doing all she can to get justice and hopes the police are too. 

Ariki was the apple of her sister's eye.

"She was very loud, very proud of who she was," Anahera told Newshub.

She was bubbly and fearless with a heart of gold. 

"She had the biggest smile, like one of the smiles that reach your eyes. I miss her smile."

At just 18 years old Ariki had her whole life ahead of her, with aspirations to see the world share her voice - and one day start her own family. 

"I really wish that she was able to fulfil those dreams," Anahera said. 

Because sadly she never got the chance. In September last year, she was the victim of a brutal murder that remains unsolved. 

"It's like they get to carry on with their lives, and they took a life."

For a long time it made Anahera angry, but she came to a point where her anger was too much. 

"So I just decided, 'Nah, yous (sic) won't have a hold over me for what you did, because you don't deserve that'," Anahera told Newshub.

But what they did to Ariki was horrific. Anahera's been told her sister's hands and feet were severed, her bones broken, and her body beaten and shoved under the driver's seat of a burnt-out car.

Police say they're not in a position to discuss these details.

The family is still awaiting an autopsy report. 

"That would give us peace of mind. We'd be able to process that and move on from all these things instead of wondering what happened."

Police said some information isn't able to be released while the investigation continues, but Anahera wants police to review their own actions. 

"There definitely needs to be competent investigation for incompetent policing," said Anahera.

Ariki was found by a dog walker in the torched car at a park on the outskirts of Havelock North.

But that was two days after officers first mistook her for a dead animal and earmarked the car for the wreckers. 

"Finding out they thought she was a sheep, nah, that's not good enough. They should've done their job properly. Cause she had gone through everything and still was left there."

Police declined Newshub's request for an interview on the homicide investigation, as they have for every request Newshub has made.

But in a statement, they said the initial response will be reviewed once the criminal investigation has been completed, adding it's an "important part of identifying opportunities for improvement and lessons learnt".

"The fact that they couldn't honour my sister, they didn't do enough and they should've. And I hope that they are right now, because I am doing everything that I am for her and I don't need a badge to do it."

While Police said the investigation is at a sensitive stage, and while no one has been arrested for Ariki's murder, Anehera can't wait for the day that happens. 

"I would've gave (sic) my own life for my baby sister. I would've told them to take me instead of her."

But now, all she can do is fight for her sister's justice.