This article is a reflection on motherhood and person-building among foreign female detainees in Penitenciária Feminina da Capital (the Capital Female Penitentiary in São Paulo). Detained far from their respective social environments and isolated behind prison walls by policies that keep them there, foreign women are subjected to numerous limitations that jeopardize their relationship with their children and other family members outside the walls. My fieldwork, done by working with two civil human rights organizations, questions prison isolation and reveals the various ways these women pass through prison walls and maintain ties with their relatives. Using an anthropological approach in this article, I intend to show how a series of relationships is established around motherhood through photographs, emails, and letters. I argue that the exchange of such things is essential for both family relationships and the constitution of the (person) foreign women, allowing them to create co-presences, negotiate maternal arrangements that go beyond the mother-child binomial, and challenge the temporal-spatial borders of incarceration in a foreign country.