The former partner of a man accused of murdering his step-daughter says she saw the girl assaulted by her mother.
Fiona Peo has been giving evidence at the trial of her former partner and the father of her three children in the High Court in Auckland.
The Crown says Michael Martin wanted to get back together with Ms Peo and was unhappy with his current relationship with Amy Lorigan when his frustration boiled over in June 2012.
Mr Martin is accused of assaulting Ms Lorigan's two-year-old daughter Leilani Lotonu'u with so much force that he ruptured an organ in her stomach. He denies charges of ill-treating and murder.
Ms Peo told the court on Tuesday that she saw Ms Lorigan acting violent towards Leilani twice. She says on one occasion, Ms Lorigan took Leilani to a bedroom and appeared to slap her in the face. On another, she hit the child in the back of the head.
Also giving evidence was Ms Lorigan's step-father Mark Chapman, who told the court the house where the mother and child were living smelled of urine and had boxes of empty alcohol bottles inside.
Mr Chapman said he helped his stepdaughter and Mr Martin to move into a state house in Manurewa but didn't like the area of the shabby, dirty house and wanted Ms Lorigan and her children to move back home.
He confirmed under cross-examination that Amy Lorigan did lose her temper, but said it was no more than normal people.