As AI systems become increasingly prevalent in our daily lives and work, it is essential to contemplate their social role and how they interact with us. While functionality and increasingly explainability and trustworthiness are often the primary focus in designing AI systems, little consideration is given to their social role and the effects on human-AI interactions. In this paper, we advocate for paying attention to social roles in AI design. We focus on an AI healthcare application and present three possible social roles of the AI system within it to explore the relationship between the AI system and the user and its implications for designers and practitioners. Our findings emphasise the need to think beyond functionality and highlight the importance of considering the social role of AI systems in shaping meaningful human-AI interactions.