Two people have been charged in relation to the suspicious death of Auckland two-year-old, Arapera Fia, Counties Manukau Police said on Tuesday morning.
Arapera died in the south Auckland suburb of Weymouth on November 1.
A man and a woman, both 21, were arrested on Monday following extensive enquiries by Counties Manukau CIB, Detective Inspector Warrick Adkin said.
The man has been charged with murder and the woman has been charged with manslaughter.
Both are due to appear in the Manukau District Court on Tuesday morning.
Officers are not seeking anyone else in relation to Arapera's death, Det Insp Adkin said.
"I want to acknowledge the hard work and perseverance by the investigation team that has resulted in these arrests," he said.
"Investigations involving the suspicious deaths of children have a profound effect on the whānau and our wider community."
Investigations can often be impeded when members of the whānau fail to come forward with information or are unwilling to cooperate with police, he added. However, Arapera's whānau assisted officers throughout their enquiries.
"I want to acknowledge Arapera's whānau who have cooperated and assisted police throughout this investigation. I also want to acknowledge those within our community who came forward with information.
"We all have a responsibility to protect our most vulnerable to prevent these tragedies."
As the matter is now before the courts, police are not in a position to comment further.