This afternoon they asked Justice Judith Potter: "To be a party to a criminal act, does the person have to be present at the time the act is committed?".
They also asked: "Can a person be a party to a criminal act after the act is committed through omission?".
Justice Potter said the simple answer to both questions was no.
The questions related to the charge of manslaughter against Oriwa Kemp and Michael Pearson and whether they knew of the types of assault being committed on Nia and whether they encouraged the alleged assaults on Nia.
This morning the jurors resumed deliberations at 8.30am. Since asking their questions, they broke for lunch at 1pm.
Last night, they were sent to a hotel for the night about 7pm after reportedly making "good progress" throughout the afternoon.
Before they retired at 1.05pm, Justice Judith Potter told the jurors she needed their patience and concentration as she summarised the case for them.
She said the Crown's argument was there were two causes of Nia's death: the alleged kicks to her head by the Curtis brothers, and the subsequent failure by Nia's mother - Lisa Kuka - to get her the medical treatment experts believe could have saved her.
The brothers are alleged to have kicked Nia on Friday, July 20, last year. She was taken to hospital the following Sunday but died in Auckland's Starship hospital 12 days later from "severe brain damage" .
Justice Potter told the jury it needed to decide if Wiremu and Michael Curtis - either as principal offender or one encouraging the other - kicked Nia in the head, causing the blood clot that killed her.
If the jury decided one or both brothers did kick Nia, it must decide also whether they had acted with "murderous intent" - that is, in kicking Nia as alleged, the brothers knew she could die but did so anyway.
The Curtis brothers deny kicking Nia.
The jury also had to decide if Kemp and Pearson were involved with the alleged abuse. Justice Potter said the jury also had to weigh up whether Kuka had breached her legal duties as a parent by failing to get Nia medical treatment quickly and for not protecting her from violence.
Jurors had also to decide if those actions posed a "real, substantive and operative cause of her death", she said.
Kuka denies knowing critical details about her daughter's alleged abuse.
Justice Potter said if jurors did not find the accused guilty of wilful ill-treatment of a child - the offences relating to Nia being spun on a clothesline and put in a clothes dryer - they were to consider lesser charges of assault.
A representative charge against the Curtis brothers included an allegation they performed "wrestling moves" on Nia - something their defence counsel referred to as "games".
"In the case of Nia, you will need to consider that it is reasonably possible that a child of 3 years old could consent to such activities."
The court heard how evidence given by child witnesses was very important to the trial. One of the children described seeing Nia "kicked to the couch" and "falling asleep" immediately afterwards, which the Crown argues was Nia falling unconscious.
Justice Potter also referred to Crown evidence from experts that indicated five areas of bruising to Nia's head which "could not have resulted from a single fall".
The jury is considering whether the injuries Nia suffered could have been from her fall from the clothesline two days before the alleged kicks in her head.
Justice Potter told the jurors they must be "dispassionate" in their decision, putting aside any feelings of anger they might have felt, and any sympathy towards Nia's family.
They were not to read anything into the fact that the five defendants chose not to give evidence.
