People living in the neighbourhoods of Nampula city, northern Mozambique, often speak of a war that is being waged at night, during which sick infants and small children figure more and more frequently as the preferred prey of malevolent ancestors, witches and new malign spirits that come at night, and who abduct and enslave them in order to harm their families. The purpose of this article is to explore what this ‘war of the night’ reveals, to understand why it is that mothers are afraid their babies and children will be stolen from the compound and, finally, to analyse the ways in which families handle their fears and apprehensions about a child's sickness. I begin this analysis of the ‘war of the night’, and the accompanying anxieties surrounding infants and children, by examining it in relation to large-scale changes that have occurred both at the micro-level of the household and in the community more generally. Specifically, the article looks at the ways in which ongoing economic and social transformations are reconfiguring gender and generational relationships, which, in turn, generates more insecurity within the household and intensifies a sense of existential threat from external forces. The article then examines the cultural logic of rumours and beliefs involving children, as a consideration of local interpretations and experiences of infancy and childhood helps shed light on local concepts of (children's) vulnerability. With the aid of three case studies, the article charts how families manage children's diseases. It shows how the uncertainty surrounding an illness is not always ameliorated by divinations or by the healing provided by women working on behalf of ancestral power. Instead, women healers often crystallize and intensify mothers’ fears, also because their medical and ritual interventions are not always effective. The article concludes by examining the reasons why these women healers are increasingly struggling to manage the evil forces haunting infants and children and to make their medical interventions effective, and the effect of this on their local authority.