If she watches, I will share: The impact of private and public self-focus on children’s sharing behavior and the moral self-concept

States with a focus on oneself, such as observing oneself (private self-focus) and being observed by others (public self-focus), are proposed to increase the saliency of own motives and evaluations by others and thereby to influence behavior. These processes become particularly relevant toward the end of early childhood, around the same age when children's moral self-concept (their view of themselves as prosocial agents) consolidates. This study advances the understanding of the role of self-focus on children's prosocial behavior by considering their moral self-concept. We investigated how private self-focus and two facets of public self-focus affect sharing behavior, the moral self-concept, and their interrelation. In a preregistered study, we assessed 5- to 8-year-olds' (N = 161, 84 female) sharing behavior and moral self-concept across four conditions. Children shared while observing themselves (private self-focus), while being observed by another child (reputation), while being observed by another child who could reciprocate later (reciprocity), or while not being observed (control). Generally, children shared more when observed by another person compared to when they were not in the focus of anybody, whereas observing themselves did not increase sharing. Children's moral self-concept was positively correlated with sharing, particularly when being in public self-focus, while mean values did not differ between conditions. The study provides novel evidence for the specific role of the awareness of others' evaluation in children's prosocial behavior. It suggests a social grounding of the moral self-concept by revealing its particular role for sharing behavior when being in the focus of social attention.