Maggie was found dead at her Onehunga home on August 7 last year.
She lived there with her mother, originally from Malaysia. Her father lives in Britain.
A post-mortem examination failed to provide clear answers about the cause of Maggie's death.
But a second autopsy was completed days later and the results led police to believe the child's death was not accidental.
Des Gilmore lived two houses down from Maggie and her mother and was close to them.
He told the Herald he was happy someone would be held to account for Maggie's death.
"She was a beautiful little girl, a lovely little girl. She was adorable.
"Every time I come home I pass the house and it's always on my mind. It is something that will never leave my mind. Maggie was a lovely, lovely little girl."
Police previously said they had been in constant contact with the victim's maternal grandparents who live in Malaysia and her aunt who lives in the United States.
The grandparents were dumbfounded when police informed them their inquiry had become a homicide investigation.
"When we found out that Maggie didn't pass away naturally, that it was somebody who did it to her ... each step is getting more and more traumatic for us, especially my wife," the grandfather said.
The child had spent about two-and-a-half months visiting them with her mother in Malaysia before she died.
