Božidarka Frajt was born Božidarka Grublješić on 11 November 1940. Born to an ethnic Bosnian Serb family, her exact birthplace is unknown due to the scarce information of her childhood. It is believed she was born in Velika Žuljevica under Kozara, and that she was taken to a concentration camp for Serbian kids in Sisak during the Kozara Offensive in 1942 along with thousands of other orphans. She was later adopted by Croatian Jews Katarina and Stjepan Frajt. At the age of 36, she found out about her Kozara heritage when a woman named Dara Grublješić identified her as her niece.