The parents of a 15-year-old girl walked out of court yesterday when they learned that their daughter's lover stood by and watched his wife send abusive texts to her.

The girl killed herself days later.

In the Rotorua District Court, Pelesasa Tiumalu, 28, was jailed for four years and three months for having sex with an underage girl.

His wife, Elina, had previously received a nine-month deferred sentence for intimidation.

The girl's mother told the Weekend Herald last night she could not understand how one was jailed and the other was not.

"Justice hasn't been done. She's the one that pushed the buttons."

After 13 months of questioning police, lawyers, courts and the coroner's office, she heard for the first time yesterday from Judge James Weir that Tiumalu knew about the abusive texts.

Tiumalu had told her during a restorative justice session that he had no idea, and he was going to leave his wife and stand by the 15-year-old when she thought she was pregnant.

"It was so unbelievable. Most of what the judge told us we didn't know. It was so devastating that we had to leave," the mother said.

She felt betrayed and lied to, and had no problem with Tiumalu being sent to jail.

She wished Tiumalu or his wife had let her know he was leaving her daughter so she could have helped her.

"The judge was right. They had so many chances to let us know."

The 15-year-old died in hospital after her brother found her on the family's bathroom floor.

The court heard Tiumalu had told the 15-year-old's parents he was 20 and had promised her father he would not have a sexual relationship with her.

"You lied ... abused that position of trust ... you exploited her," Judge Weir said. The consequences had been tragic.

Outside the court, Elina Tiumalu, who is six months pregnant and the mother of Tiumalu's 2-year-old daughter, said she had a lot of regrets.

"I feel sorry for those texts. My emotions got the better of me, I am only human."

She said she would stick by her husband and follow him to Samoa if he was deported after his sentence.additional reporting

- Additional reporting by NZPA