This book provides a detailed look into the social world of infants and toddlers and explores the consequences of that environment on learning and socio-emotional development. Drawing on long-term ethnographic fieldwork and systematic observation in a rural community in Madagascar, it shows that children there grow up in dense social networks from birth, surrounded not only by parents and siblings but also by peers, cousins, aunts, grandparents, neighbours, and more. It challenges dominant parent-centric frameworks that assume socio-emotional development begins in relationships with parents, which form the basis for a gradual expansion of childrens social relations. By contrast, the multiple coexisting but distinct social relationships of young children in this study provide parallel developmental pathways. This enables them to acquire simultaneously hierarchical-interdependent and egalitarian-autonomous modes of relationships, emotion, and self. The book presents a powerful critique of mainstream developmental science and calls for a broader, more inclusive understanding of early childhood across cultures.