Responsive to perceived high risk of HIV infection by sexually active youth, several South African sexual health-promotion campaigns have used media targeting mothers, instructing them on how sex should be talked about with their children to 'risk-proof' them. A Foucauldian approach to the normative apparatus of family–sexuality–risk finds mothers positioned as pivots between 'public' (health, economy, culture) and 'private' (family, childrearing, sex) apparatuses, tasked with appropriately socialising a new generation of sexually responsible, HIV-free citizens. This paper uses a reading of interactive discourse from (racially and gender) mixed groups of parents who, as professionals and postgraduate students in a university context, discussed their own childrearing practices in response to a particular didactic media text about sex-communication. In a way different from traditional media-reception studies, this discourse analytic reading of parents' engagement with risk-expertise examines how mothers especially are persuaded (or not) to adopt particular childrearing practices in the context of an HIV epidemic. Using a Foucauldian argument about subject positioning, this paper examines how the parents positioned themselves in relation to the expertise offered in the stimulus material, as well as how they positioned one another during the group discussions. The analysis explores the partial buy-in to expert Western psychological techniques concerning talking with children about sex openly and often, and how this appropriation is negotiated in contextual family situations that are gendered, raced, classed and acculturated.