Like his younger brother Gilvan, was born to a marginalized family in the favela of Terra Encantada (Dreamland!) in greater Rio de Janeiro. His childhood was difficult, being raised by a single mother in poverty, and in a violent environment. After attending Camp Hazen in 2006 and 2007, Gilmar moved away from Terra Encantada in 2008. However, inspired by his training and experiences at Camp Hazen, he enrolled in university in Rio and worked hard at improving his English. He subsequently worked in a bank in the city center before deciding he really wanted to teach. After teaching many young children at Terra Encantada, he earned his teaching credentials and is now a teacher and staff scheduling administrator in the public school system.