The Curtis brothers' father, William Curtis, has just been released from jail after being convicted of abusing the toddler as well.
She had suffered months of horrific abuse before the brothers forcefully kicked her in the head causing fatal injuries. Nia died in Starship Children's Hospital in 2007.
Since Kuka was jailed she has made two applications to the Parole Board for release.
One in October 2011, when the board requested she undergo a psychological report and drug and alcohol counselling which she was at first reluctant to do, and the second in April this year when it was decided she would undertake drug and alcohol counselling or she would remain an undue risk to the safety of the community.
She is due to go before the Parole Board again in March when she would have served four years.
Mr Winters said Nia's abusers or any other child abusers should never be allowed to live a normal life or this type of horrific abuse would continue to haunt our communities.