This comprehensive Handbook will change the current mindset about sibling relationships—from a relationship of secondary importance to parent-child relationships—to one that reflects the many ways siblings contribute to individual development and family functioning throughout the life course and across diverse cultural contexts. As it presents the growing body of research on sibling relationships, it offers a new sibling-informed theoretical framework that challenges traditional notions of the sibling bond as one based on hostility, rivalry, and conflict. New directions are offered for research and practice that will address the real needs of families. This Handbook is relevant to all researchers and mental health practitioners.

Laurie Kramer, PhD is Professor of Applied Psychology at Northeastern University and is the Founding Director of the Family Resiliency Center at the University of Illinois. Her longitudinal research on the early development of sibling relationships has led to the development of an evidence-based intervention program to strengthen children’s sibling relationships that is serving families from around the globe. She is a Licensed Clinical Psychologist with expertise in child and family therapy. An award-winning teacher and former academic dean, she has also devoted much of her career to advancing undergraduate and graduate education.

Nina Howe, PhD is a Distinguished Professor Emeritus in the Department of Education, Concordia University, Montreal. She held the Concordia University Research Chair in Early Childhood Development and Education (2007-2023). Her areas of research include children’s sibling relationships (pretense, conflict, teaching, imitation), children’s play, the social-cognitive development of preschool and school-aged children, and early childhood education. She is a prolific writer whose work has been supported by numerous granting agencies. A former school counsellor and special education teacher, she has applied her rich experiences to support the educational mission of preschools and childcare centers. 

Brenda L. Volling, PhD is the Lois Wladis Hoffman Collegiate Professor of Psychology at the University of Michigan. Her research focuses on early social and emotional development, siblings, parent-child interaction, and family relationships. She has conducted extensive research on the role of fathers and children's development and continues to work with international collaborators, students, and post-doctoral fellows to advance research in father-child relationships. She is also the Principal Investigator of the Family Transitions Study (FTS), a longitudinal investigation examining changes in family functioning and the firstborn’s adjustment after the birth of a baby sibling, which has received funding from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and the John E. Fetzer Foundation.