The Crown is challenging a sentence of seven years in prison given to the killer of a Palmerston North child.
Three-year-old Cash McKinnon was found unconscious with head injuries at a Palmerston North house in August 2009. She died in hospital the next day.
Sean Donnelly, 23, was sentenced in the High Court in Palmerston North in March to seven years in prison for manslaughter.
Donnelly hit Cash after she had put a toilet roll into the toilet bowl.
When the little girl told Donnelly she didn't have to listen to him, he spun her around by the ankles, because he did not want to hit her again.
The Solicitor-General's office confirmed it would challenge the sentence in the Court of Appeal and described it as being "manifestly inadequate", Radio New Zealand reported.
The Sensible Sentencing Trust earlier slammed the sentence saying it was pathetic.
NZPA