There seems to be a broad agreement that curiosity is important in education. However, current research often seeks to answer the question of how best to nurture curiosity and fails to ask the normative question of why this should be done. A closer look reveals that the reasons for justifying the importance of curiosity vary, with some theorists pointing to its role in cognitive development as a starting point for learning, and others praising it as an element of democracy and a child's right to participation. Most of these approaches understand curiosity as an individual urge or desire for knowledge. In contrast, this article will examine a relational understanding of the concept by focussing on social curiosity. Instead of following a cognitive developmentalist, intellectual virtue or emancipatory approach to valuing curiosity, I will employ relational ethical theory. The argument then explores a possible analogy between social curiosity and the concept of sovereign expressions of life, as developed by the Danish philosopher and theologian K.E. Løgstrup. By drawing on his relational ethics, the article aims to expand the theoretical grounds on which curiosity can be normatively legitimised in education. With children spending longer and longer hours in educational, structured and adult-led settings, I conclude with a twofold normative claim: Social curiosity should be a part of all relations in education and its absence should lead to an ethical demand. In addition, an awareness of the actual deeds through which social curiosity is realised is also a topic that must be addressed by educators.