Maria das Graças (née Silva) Foster was born on 26 August 1953, in Caratinga, Minas Gerais in southeastern Brazil. By the time she was eight years old, Foster's family moved from Caratinga to a favela, also known as a shanty town community, outside of Rio de Janeiro. The area, known as Complexo do Alemão was extremely poverty stricken and ridden with crime. Overpopulation, drug trafficking, unsanitary conditions, malnutrition, pollution, and diseases, along with high mortality rates remain widespread in the poorer favela communities. The conditions in Complexo do Alemão necessitated consistent occupation and monitoring by Brazilian security forces.[2]
Foster credits her success and motivation to excel to the support she has received from her mother, yet characterizes her childhood as "happy, joyful but very difficult".[7] In an interview with O Globo, she said, "I lived in the Complexo do Alemão for 12 years, lived with domestic violence in childhood and faced difficulties in life. I have always worked to help support my mother and my children and pay for my studies. Willpower is everything for me. I was never afraid of work."[8] She never knew if she would be able to continue going to school. In order to pay for her school books, she often collected recyclable trash that had been dumped in the streets.[9] During this time, her neighbors were immigrants from Portugal, who would occasionally call on Foster for assistance. In exchange for extra money, she would often help them with reading and writing letters and acclimating to the Brazilian culture.[2][10]
Despite her national prominence and wealth, Foster continues to live in an apartment in Rio de Janeiro's Copacabana neighborhood, with her husband, British-born, Colin Foster, and her two adult children. Foster's home apartment is boxed in by large seemingly ominous apartment buildings, and surrounded by the hillside favelas. In spite of her ability to afford luxuries that would reflect her standing in the country's social, political, and professional circles, she chooses to travel by taxi, rather than own a car. She is easily recognized and popular with local drivers, who always greet her with a smile, in an effort to get her business.[10]
She has been at the center of corruption accusations at Petrobras.