A 25-year-old man has been charged with the murder of an eight-month-old Bella Richardson in Whanganui in 2016.
He appeared in Masterton District Court on Thursday and has been remanded in custody.
Bella died at a property in Whanganui on November 7, 2016 and the accused is known but not related to her.
Detective Senior Sergeant Paul Baskett hoped the charge would bring some closure for Bella's family.
"This has been a protracted investigation due to the complex nature of the medical evidence," he said.
"I would like to thank all those who helped with the investigation."
Judge Barbara Morris granted the man interim name suppression until his next appearance in the High Court.
Defence lawyer Frank Minehan said the incident was of "historic nature" and he was concerned for the man's mental health.
The charge would have come as "a deep shock" to his family, Minehan said.
The defendant's mother supported him in court on Thursday afternoon.