Sonia is a member of the Maramanindji people from the Daly River region of the Northern Territory. She is the second eldest of 12 children and lived her early years on cattle stations in the Top End of Australia where her father worked as a stockman.
Sonia’s schooling included correspondence lessons taught by her mother. Schools on cattle stations and then in a small town of Adelaide River. After primary school, Sonia was sent to boarding school at Loreto Abbey, Mary’s Mount in Ballarat.
As a mature age student, Sonia commenced undergraduate studies at Monash University and post-graduate studies at Melbourne University, where her Masters thesis was on the intellectual and cultural property rights of Indigenous peoples.
Prior to joining the United Nations Permanent Forum on Indigenous Issues in November 2005, Sonia was a Senior Lecturer in the School of Australian Indigenous Knowledge Systems, Charles Darwin University in Darwin, where she taught in a number of subjects including Northern Perspectives (a political, social and environment overview of Northern Australia), Indigenous History and Contemporary Indigenous Studies. Sonia worked at the United Nations in New York as a Social Affairs Officer for eleven years. During this period, Sonia’s focus was on the myriad of issues facing Indigenous peoples around the world.
In 2017, Sonia returned to Australia (after retiring from the United Nations) with her Cocker Spaniel called Skippy and currently lives in Alexandria. Sonia has some knowledge of films and television because her daughter, Penny Smallacombe is a graduate of AFTRS.