Co-design in practice can be extremely difficult, especially when multiple stakeholders are involved. In this research, we reflect on ways to produce cooperation between low-income mothers, nurses, and doctors, as they work with researchers to co-design an artifact to alleviate communication gaps in a South African neonatal intensive care unit. We describe the strategies used to mediate and foster cooperation between these stakeholders; cooperative prototyping techniques can foster collaboration, disentangle participation and enhance participant creativity in spite of power differentials and initial feelings of disconnection. We argue for flexible, responsive design practices that foster readiness to design with other stakeholders