In November 2020, she was selected as the SNP's candidate for the Ayr constituency in the 2021 Scottish Parliament election.[8] In May 2021, she was elected as a member of the Scottish Parliament for Ayr with a majority of 170 votes, defeating the incumbent John Scott who had been the Scottish Conservatives' longest serving MSP.[9]
Born in London to Scottish parents, Brown emigrated to Sydney, Australia when she was three years old.[3] After working in Spain, Italy, London and Scotland,[13] she moved to Ayrshire—where her parents are from—in 1999.[14] Brown has four children (including a step-daughter),[3] with her youngest being born when she was 44 years old.[6] In 2016 she founded the South Ayrshire Babybank and remains a volunteer for the organisation.[15]