The mother of the children and the man accused of wounding them both pleaded guilty on Thursday.
Emergency services were called to the scene just before 6pm on Thursday.
"Glass went flying everywhere".
A postmortem of the body was conducted on Thursday morning.
A man and woman, both 25, will face court today.
There is no ongoing risk to residents.
Police, Oranga Tamariki, foreign affairs and immigration officials are looking into concerns.
Both men have now been jointly charged.
Police say one person has been taken into custody.
An investigation is underway.
It comes as police separately arrested three men in a different shoplifting case, who stole $750 worth of meat at the weekend.
The charges follow a police raid of the man's home earlier this month.
Two people were killed and three others injured in a 100-person brawl at the weekend.
Police believe the injuries were inflicted deliberately.
Police are considering charges.
The man faces a charge of wounding with intent to cause grievous bodily harm.
"This seems to be something that just happens on a regular occurrence now."
Two are dead and another three seriously injured.
The public has been asked to come forward if they noticed suspicious behaviour at two Lower Hutt properties recently.
He was discharged without conviction.
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