RITA Knuchel has seen 23 prime ministers take office in her lifetime and yesterday voted in her 31st federal election. 
Today, Mrs Knuchel, right, celebrates her 100th birthday alongside her 103-year-old sister Thelma Badman, left, who has voted in 32 federal elections.
Mrs Badman said that every election was important and people needed to think carefully before voting. "I feel it's a necessity that everyone votes and thinks well about it before they do," she said.
The pair were born in Moonta and grew up in Fowlers Bay on the far west coast, before moving to Adelaide to go to school in Westbourne Park.
They celebrated Rita's birthday with about 70 friends and family members at her daughter Judy Staker's house in Glenelg."They've been wonderful role models to me and they've led very good, clean lives totally devoted to family," Mrs Staker said.