Brown-Pereira was born on Rarotonga in the Cook Islands and grew up in Papatoetoe, Auckland, New Zealand. She attended the University of Auckland and completed a bachelor of arts degree in political studies and sociology. From 1995 to 1997 she worked for the Cook Islands Consulate General in Auckland, then moved to Rarotonga to take up a position at the Cook Islands Ministry of Foreign Affairs and Immigration. In 2000, she returned to New Zealand as First Secretary to the Cook Islands High Commission in Wellington. In 2004 she moved to Apia, Samoa, and worked at the National University of Samoa as an Executive Administrator. She moved to the United States in 2010, returning the following year to Samoa where she worked in project management. In 2014 Brown-Pereira was appointed Executive Officer at the Secretariat of the Pacific Regional Environment Programme. In 2018 she was part of the Cook Islands delegation to the 2018 United Nations Climate Change Conference.