[1][2] Ecclestone was born in Rijeka, where her Serb parents—Jovan "Jovo" Radić and Ljubica Malić from Maglajani and Riječani, respectively, both villages within the Laktaši municipality, PR Bosnia and Herzegovina—had settled shortly before her birth in search of expanded job opportunities.

[3][4] The family soon moved back to northern Bosnia to her father's village, meaning Slavica would spend the majority of her childhood in Maglajani.

[3] After her parents divorced when she was seven 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.

[12] She ranked 194 in The Sunday Times' Rich List after she was awarded an estimated £740 million from her divorce.

[13] In December 2019, she put her Chelsea mansion up for sale for more than £100m after daughter Tamara's home in Kensington Palace Gardens was raided and jewels worth £50m were stolen.