Ecclestone was born in Rijeka, PR Croatia, FPR Yugoslavia where her Bosnian Serb parents — Jovo Radić and Ljubica Malić from Maglajani and Riječani, respectively, both villages within the Laktaši municipality, PR Bosnia-Herzegovina — had settled shortly before her birth in search of expanded job opportunities. The family soon moved back to northern Bosnia to her father's village meaning Slavica would spend the majority of her childhood in Maglajani. After her parents divorced when she was only 7 years old, being raised by her mother Ljubica, Slavica was taught to "not do to someone else what you wouldn't want to be done to yourself."