In the latter instance too, the child's mother and her boyfriend have been found guilty, along with a brother of the boyfriend.
Nia Glassie died on August 3, 2007, from massive bleeding between her skull and brain, 12 days after being taken to hospital.
In the months leading up to her death the toddler had suffered horrific abuse while being brought up in an environment where she was often surrounded by several people.
The catalogue of the tortures inflicted on the helpless child makes a sickening reading:
* Kicked in the face, causing her nose to bleed;
* Hit, slapped, punched and jumped on;
* Objects such as shoes thrown at her;
* Verbal insults, for example continually being told she was ugly;
* Forced into a television cabinet drawer;
* Dragged through the sandpit half-naked;
* Shoved into piles of rubbish;
* Made to bathe in cold water in mid-winter;
* Folded into a sofa and sat on;
* Flung against the wall;
* Held high in the air and dropped to the floor;
* Used for adult wrestling moves copied from a Playstation game;
* Whirled rapidly on a rotary clothesline until flung off;
* Put into a tumble dryer and spun on high temperature;
* Had her head and feet dangled into the fireplace when the fire was lit;
* Kicked repeatedly in the head because she was crying;
* Left lying in a coma for 36 hours without medical attention.
Wiremu Curtis, 19, and Michael Curtis, 22, were found guilty in Rotorua High Court this afternoon. Wiremu Curtis was the boyfriend of Nia's mother, Lisa Kuka, 35, who was found guilty on two manslaughter charges relating to a lack of protection and failure to seek medical help for her critically injured daughter.
Nia's cousin Michael Pearson, 20, and Michael Curtis' partner Oriwa Kemp, 18, were found not guilty of manslaughter in relation to the death.
They were, however, found guilty along with the Curtis brothers on various other charges.
The Curtis brothers and Kemp were found guilty on ill-treatment charges, specifically relating to swinging Nia on a clothesline, and also on general ill-treatment charges.
Pearson escaped a conviction on the general charge.
The brothers and Pearson were also found guilty of charges relating to putting Nia in a tumble drier.
Media reported the Curtis brothers were visibly upset when their guilty verdicts were returned and needed to be restrained by prison guards.
The five had been on trial for four weeks and the jury had over 20 charges to consider before returning the verdicts.
The case surrounding Nia's death caused a national outcry when information about it emerged last year, and feelings were inflamed as finer details of the abuse emerged throughout the trial.
Lawyers for Pearson and Kemp distanced their clients from the worst of the abuse, saying they were either not directly involved or not present at all when the worst of it occurred.
Kuka's lawyer described her as a hard working mother who wanted the best for her children but had made a big mistake in pairing up with a then 17-year-old Wiremu Curtis.