The eldest sister of a young boy who was critically injured says their mother told her not to tell anyone she had "whacked" him.
Itupa Julie Mikaio is facing charges of wounding with intent to cause grievous bodily harm and failing to provide the necessaries of life at the High Court in Auckland.
Three-year-old Benjamin Mikaio was admitted to hospital in June last year suffering head trauma, a broken pelvis, broken hands and bruising so severe it had bled into the muscles. He has yet to fully recover.
His mother has admitted inflicting the injuries to his body, but not his head.
The court was told on Tuesday that the boy's 12-year-old sister woke to his cries early one morning in June last year.
The girl says she saw her mother hitting the boy in the head because he had wet his bed again. Afterwards, he tried to get up and walk, but collapsed and became unconscious.
The court was told the girl's mother prayed for him to wake up, but did not seek any help for him until 1.30pm that afternoon.
The girl said her mother told her not to tell her father or anyone else what she had done.
Earlier, the defence lawyer for Mrs Mikaio suggested in court that one of her daughters was an unreliable witness.
The girl told police in her initial interview with them that she did not know how her brother came to be injured.
But in her second interview she said that her mother beat him with part of a vacuum cleaner before throwing him head first onto the floor.
The defence suggested in court on Tuesday that information was neither reliable nor credible, as the girl was influenced by police, who were keen to prove the allegations against Mrs Mikaio.