The Impact of Emotion Regulation and Individual Traits on the Nature of the Next Older Sibling’s Relationships with Their Toddler/Infant Sibling

This research examined the role of self-regulation and other individual factors in the development of siblings’ relationships in a family construct when one of the children is under 5 years of age and their closest in age younger sibling is an infant or toddler. For this purpose, we recruited 85 families; the mother in each family completed the Sibling Inventory of Behavior (SIB) and emotional regulation questionnaires for the target (older) sibling. In addition, age and gender data on the children were collected. The results show that ambivalent relationships characterized siblings’ interactions in early childhood in this specific family constellation. Namely, the elder siblings expressed both friendship and rivalry toward the younger ones. Analysis of the association between behavioral expression trends and emotion regulation and background factors revealed that self-regulation is positively associated with tendencies toward friendship. However, increasing age of the oldest sibling was associated with reductions in the elder sib’s emotion regulation, subsequently hampering the development of friendship tendencies toward the younger sibling. Moreover, an association was observed between the age of the younger sibling and the tendencies toward friendship and rivalry. Furthermore, the age gap between the siblings impacted the direction of the relationship. Namely, increases in the age gap led to a reduction in both friendship and rivalry approaches. The conclusion of the study highlights the importance of accepting the ambivalent interaction of siblings and the need for parental involvement to facilitate the improvement of emotion regulation skills and the acquisition of strategies for solving problems in dispute situations for the child.