Sibling relationshipsare full of sociological intrigue. Siblings can pervade our everyday lives, shapingour identities and relationships through the life course, tapping into profound questions about who we are and who we can become, about family, relatedness, self and time. It is surprising then that the role of lateral ties between siblings has received relatively little sociological attention. Drawing upon innovative qualitative data sources and focussing on four key themes in sociological thought – self, relationality, imagination and time –Siblings and Sociology addresses this omission by exploring the sociological significance of siblingship. Grounded in theories of relatedness but spanning theoretical work on generation, life course, emotion, sensory worlds, normativity and identity, Siblings and Sociology demonstrates how and why siblings matter, asking what sociological insights can be gained by using siblingship as a lens through which to re-examine these familiar sociological ideas.