A source told the Herald that her injuries revealed the car that hit her was not travelling at speed. Neither the vehicle nor the driver was at the property when Mila was found.
Mila, who is survived by four sisters, would have turned 2 in October.
Yesterday, a large number of relatives gathered at the home of Ms Broughton and Mr Tamihana. The family were not ready to speak publicly about Mila's death.
Detective Sergeant Eugene Pickett said police would continue speaking with members of Mila's family and neighbours to establish what happened to her her.
"We are mindful that this is an extremely difficult time for Mila's family and as our investigation continues, supporting her family through this is also a priority," he said.
Tributes to Mila were flowing on Facebook.
Sariah Tamihana said she was devastated. "Love n hugs to all my whanau at this time. You are all in my prayers," she wrote.