The mother of a toddler who was subjected to inhumane torture in the lead-up to his murder has had her 44-year jail term cut by six years.
The three-year-old boy had only been living with his mother and stepfather for seven weeks when he died in August 2014 in the NSW town of Oberon.
Three years later, the then 43-year-old was jailed in the NSW Supreme Court for 44 years with a non-parole period of 33 years.
The Court of Criminal Appeal on Wednesday cut her sentence to 38 years, with a non-parole period of 28 years and six months,.
The court found the sentencing judge failed to apply legal principles relating to her depression and mental illness.
Joseph had lived with extended family for three years but in the short time he was with his mother and stepfather, he had his head slammed in a cupboard, eyes covered with duct tape and naked body shut in a freezing esky.
"During that period, he was subjected to sustained episodes of physical, psychological and verbal abuse, ultimately culminating in his death," the Appeal Court said.
The couple admitted regularly abusing the boy but maintained he died after tripping over a rope tied to the family dogs during a trip to the local park.
The jury rejected their explanation, finding both guilty of murder.
Lifeline 13 11 14
beyondblue 1300 22 4636