Through the letters brothers and sisters wrote to each other over the course of nearly a century (1840-1920), Annette Atkins reveals the inner workings of ten nineteenth-century families, illuminating their everyday lives and central relationships. Drawing on the insights of Alfred Adler and others, Atkins examines the varying dynamics of "warm" and "cool" families, clothing theory in the human relations revealed by the letters. She looks at families located in various regions, families headed to the frontier, obscure families, and prominent names such as the Blairs of Washington, D.C.

The correspondence between brothers and sisters sheds light not only on the emotional fabric of their families but also on the way they learn to express themselves. Atkins shows how siblings tutored each other in friendship, authority, cooperation and competition, dependence and independence. They learned from each other how to express (or repress) emotions, how to see themselves, and how to be in the world.

By exploring individual families in intimate detail, We Grew Up Together counters simplistic notions of traditional family life in an earlier era. Through family upheaval, abandonment, divorce, death, and conflict, siblings sustained vital familial links with each other, providing connection, stability, permanence, and emotional grounding that often persisted throughout their lives.