DNA analysis showed that the remains are that of two-year-old Khandalyce Kiara Pearce, South Australia Police (SAPOL) said
in a press conference Wednesday.
They also revealed that a body found dumped in Belanglo State Forest in the state of New South Wales in 2010 belonged to the girl's mother, 20-year-old Karlie Jade Pearce-Stevenson.
"You should think of this investigation as being at the start as opposed to the end," SAPOL's head of Major Crime, Detective Superintendent Des Bray said.
The investigation started in July when the child's body was found by a passerby alongside the Karoonda highway in South Australia.
Near the body was a faded, greying black suitcase, a quilt, and items of children's clothing, including a black party dress and a Dora the Explorer T-shirt. At one point the child had been stuffed inside the suitcase, police said.
Officers issued a public call for information to identify the child, but it wasn't until earlier this month that a phone call to a crime hotline suggested that it may be Khandalyce. DNA testing confirmed her identity.
Forensic testing also led police to identify her mother, who had also suffered a violent death, they said.
Missing Person Report withdrawn
The mother and daughter weren't formally registered as missing.
"Ms Pearce-Stevenson and Khandalyce are from a loving family. Both were born in Alice Springs but we know that during 2008 they moved away from their family and started to travel," Detective Superintendent Bray said.
Over the next year, contact between the two and their family started to become less frequent, and in September 2009 Pearce-Stevenson's mother filed a missing person report.
However, a week later it was withdrawn.
"It is understood that report was closed on 10 September 2009 after it was believed Ms. Pearce-Stevenson was safe and well but did not want family contact," Detective Superintendent Bray said.
Investigation 'at the start'
Police are now trying to piece together what happened to the mother and child, who were last seen in November 2008, driving along the Stuart Highway near Coober Pedy, north of Adelaide in South Australia.
"We are calling on every community across Australia to provide any information they have to police that may help solve this crime. If you know something, please contact police now."
They want to hear from landlords, motels and caravan parks where the pair could have stayed.
"Those responsible for this crime are truly evil and remain amongst us in the community and must be held accountable for what they have done," Bray said.