Investigators believe the mother died late Monday in the home in Yarraville where she lived with her son, The Age reported. A passerby noticed her body through a window Wednesday.
Police launched a homicide investigation but later said the mother was not the victim of foul play. The boy was badly dehydrated but had no other obvious physical problems.
Sgt. Mark Anderson said the boy kept grasping police officers.
"He was very clingy, he didn't want to be let go," Anderson said.
Neighbors said the dead woman appeared to be a devoted mother.
"She constantly doted over her little boy," said Brenton Dohse. "He's had a troubled start in life, I hope it works out for him."
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