Observing social exclusion can be a distressing experience for children that can be followed by concerns for self-inclusion (self-concerns), as well as prosocial behavior to help others in distress (other-concerns). Indeed, behavioral studies have shown that observed social exclusion elicits prosocial compensating behavior in children, but motivations for the compensation of social exclusion are not well understood. To distinguish between self-concerns and other-concerns when observing social exclusion in childhood, participants (aged 7–10) played a four-player Prosocial Cyberball Game in which they could toss a ball to three other players. When one player was excluded by the two other players, the participant could compensate for this exclusion by tossing the ball more often to the excluded player. Using a three-sample replication (N = 18, N = 27, and N = 26) and meta-analysis design, we demonstrated consistent prosocial compensating behavior in children in response to observing social exclusion. On a neural level, we found activity in reward and salience related areas (striatum and dorsal anterior cingulate cortex (dACC)) when participants experienced inclusion, and activity in social perception related areas (orbitofrontal cortex) when participants experienced exclusion. In contrast, no condition specific neural effects were observed for prosocial compensating behavior. These findings suggest that in childhood observed social exclusion is associated with stronger neural activity for self-concern. This study aims to overcome some of the issues of replicability in developmental psychology and neuroscience by using a replication and meta-analysis design, showing consistent prosocial compensating behavior to the excluded player, and replicable neural correlates of experiencing exclusion and inclusion during middle childhood.