The Curtis brothers, Michael's girlfriend Oriwa Kemp and Nia's cousin Michael Pearson also face multiple charges of assault.
One juror cried as Mr Pilditch outlined the allegations against the four, including that they:
* Forcibly placed Nia on a clothesline and spun her around until she fell off, twice repeating the action while standing around laughing.
* Put her in a tumble dryer and turned it on, standing by laughing.
* Subjected her to wrestling moves called "pedigrees", "tombstones" and "choke slams" allegedly inspired by World Wrestling Federation television programmes and a PlayStation video game called SmackDown! vs Raw.
* Forced Nia to take cold baths and then dressed her in soiled clothes.
* Made her sit in a sandpit with no clothing on her bottom half.
* Forced the toddler to standoutside in the cold for hours.
Mr Pilditch said that the second time Nia was forced on to the clothesline, she was picked up by the ankle.
"People were laughing at Nia, saying, 'Good job, you shouldn't have complained'."
The fatal kicks were allegedly inflicted on the night of Friday, July 20, and Nia was said to be "deeply unconscious" when her mother bathed her about 4am on the Saturday after she wet her bed.
The Crown alleges Kuka committed manslaughter by failing to get medical help for Nia and failing to protect her from violence, saying she knew "full well" about the assaults but did nothing to prevent them.
She and the others have denied the allegations.
Michael Curtis' 21st birthday party was held at the Frank St house on Saturday, July 21, and during the day people observed Nia lying in her bed suffering fits and fighting to breathe.
Curtis allegedly referred to the fits as Nia doing "the funky chicken".
She was taken to an aunt's house in the evening, and eventually to Rotorua Hospital the next morning when the aunt, Louise Kuka, panicked because Nia was grinding her teeth and her jaw could not be prised open.
The 3-year-old never came out of her coma and died in Auckland's Starship hospital 12 days later.
Police officers gave evidence of going to the house on the morning of July 20 to execute a search warrant for a burglary and finding Nia lethargic.
Detective Constable Dennis Nairn examined the dryer in which the toddler was allegedly placed and said he found a strand of hair trapped at the rear between the stainless-steel barrel and the filter cover.