This paper conducts an inductive case study to build a theory on the role of family in both the host and home countries in immigrant entrepreneurs' attempts at creating entrepreneurial opportunities. We used the perspectives of the opportunity creation process and family social capital. We relied on data collected from four cases of immigrant entrepreneurs from Lebanon, Syria, Cameroon and Mexico who have established businesses in Sweden. The paper identified three sources of family social capital: family duties, family trust and family support as being relevant for creating opportunities. While family duties triggered the process of forming an entrepreneurial idea, this process was advanced by the existence of family trust. Family support was then the building block for launching an entrepreneurial idea. By identifying these three sources of family social capital, we show that families in the host and home countries contribute to immigrant entrepreneurs' opportunity creation.