The tot was found dehydrated near her mother's corpse at their home in Wagga Wagga on Friday.
Her 36-year-old mum has not been named, but her tragic death has left the close knit community devastated.
One of her neighbours told AAP: "You hear about people dying and not being discovered for months - that would never happen here. But we are still so sorry it happened the way it did."
The authorities went to the woman's home when neighbours raised the alarm after becoming concerned they had not seen the woman.
The baby was said to be showing signs of shock when found, and a paramedic at the scene described her as being 'lethargic and pale'.
Ambulance Inspector Eamonn Purcell told AAP: "She wasn't saying much, she wasn't displaying much emotion."
He said the little girl might have survived her ordeal by eating chocolate Easter eggs.
Mr Purcell said they could not be sure how long the toddler had been on her own, but said that locals feared her mum had died up to five days before she was found.
"You've got to feel for this two-year-old who might have been alone days and nights in this house," he said.
A neighbour told reporters she wished she'd checked on her sooner, saying she had become concerned after seeing washing left on her line, but that it was another neighbour, a nun, who raised the alarm by contacting the deceased woman's church.
The mother was described as "a wonderful woman and a fantastic mum".
A spokesperson said the little girl was in Wagga Wagga Hospital in a satisfactory condition but was being closely monitored.
Detective Inspector Jeff Barr said people must contact the police if they have concern for a neighbour:
"We ask the community to notice their neighbours, especially elderly neighbours or people who are vulnerable, and if you are worried or you haven't seen them in a few days, contact police," he said.
The police are waiting for a post-mortem examination to determine the cause of death, and say it is currently too early to say whether or not it was suspicious.