The judge in the long-running Robert Xie trial has urged the jury to remain calm and not apply pressure to one another after they indicated they have reached an "impasse".
Xie has pleaded not guilty to murdering five members of his wife's family at their North Epping home in July 2009.
After nine months of hearing evidence and 10 days of deliberations - some of which have involved the jury being sequestered in a Sydney hotel - the 12 members indicated on Friday that they are unable to reach a verdict.
Then, after lunch, the jury left for the day after a one of them fell ill.
In sending them home for the weekend, Justice Elizabeth Fullerton urged them to remain calm.
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"I'm not so naive to think where there is disagreement there might not also be raised temperaments, raised voices, strong words.
"However, that is to play no part in your continuing deliberations.
"I'm not aware of any outburst but I don't want it to start now. I don't want any one of you to apply pressure to any other of you."
The comments came after Justice Fullerton directed them to retire again and see if they can reach a unanimous verdict, saying: "I do have the power to discharge you ... but I will only do so if I'm satisfied there is no likelihood of genuine agreement being reached after further deliberations."
Xie, whose trial began in February this year, is accused of creeping into his brother-in-law Min Lin's home in the early hours of July 18, 2009, and, in the dark, killing him and his wife Lily.
He is then alleged to have murdered Lily's sister Irene before killing his two nephews Henry, 12, and Terry, nine.
Xie denies the allegations.
