Ngunnawal elder Aunty Violet Sheridan believes Australia rejecting an Indigenous voice to parliament would be a crushing blow to her community.
"It will take us back 65,000 years because things are not gonna change for us, which is sad," she told reporters outside Parliament House in Canberra on Friday.
"We need to unite all Australians and work on this together, and move forward with reconciliation."
Surrounded by 'yes' campaigners on the final day before Australians vote, the 68-year-old's emotion was plain to see.
Acknowledging polling data was pointing to an unsuccessful referendum, she pleaded with non-Indigenous Australia for a chance to help fix issues such as the life-expectancy gap and over incarceration.
"My granddaughter is just a baby. When she is 68 years old and her granddaughter is standing beside her, will this gap be closed? Will our incarceration in our jails be less?" Aunty Violet asked.
"People need to understand it - we're not coming to take your backyards, we're not coming to claim compensation, we're asking for a voice to advise the government about us and our next generation for the future so this gap is closed."
The Ngunnawal elder spent a year on the Aboriginal and Torres Strait Islander Commission, and believed it did "some good things for communities" before former prime minister John Howard abolished it in 2005.
"We have a chance now to vote 'yes', and support us to make changes, to let us speak for ourselves ... to advise the government where they've been going wrong," she said.
Yes23 campaign director Dean Parkin wouldn't be drawn on Aunty Violet's assertion a 'no' result would set Indigenous people back 65,000 years, asking for the votes to be counted before the political post-mortem begins.
"We've been at this for decades ... let us have the opportunity to do what we said all the way through, which is put this to the Australian people," he told reporters.
"There'll be a year's worth of analysis about what might have been or what could have happened, but let's just use these last few hours to focus on those people that are yet to cast their vote."
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Australian Associated Press