Prior research shows that children's reasoning about robots tests the boundaries of their ontological commitments. In this study, we investigated the potential role of parent-child conversation in guiding children's developing understandings about robots. Parents and children (3- and 5-year-olds) engaged in a play session in which they talked about a robotic dog, a live animal (a rodent), and a human-made artifact (a toy car). Afterwards, participants reasoned about whether each item had a set of animate (e.g., biological, psychological, sensory) and artifact (e.g., human-made, breakable) properties. Findings revealed that parents and children spontaneously talked about the robotic dog using both animate and artifact properties during the play session. Furthermore, parent talk in the play session had the most influence on children's reasoning when the properties under consideration were less well-established in children's thinking and/or not easily identified by visual cues (i.e., psychological and sensory). (C) 2016 Elsevier Inc. All rights reserved.