The research team focused on middle childhood, a developmental window roughly spanning the ages of six to twelve, when peer relationships begin to rival family relationships in emotional importance. During this period, children increasingly build reciprocal, intimate friendships that serve as training grounds for empathy, conflict resolution, and social support. The participants in the study had a mean age of 10.4 years, with a standard deviation of 0.48, placing them squarely in this formative stage. At this age, having a mutual best friend is not merely a pleasant feature of school life; it is a developmental resource associated with protection against victimization, better adjustment to school transitions, and lower levels of internalizing problems. Understanding what qualities children bring to these friendships—and how those qualities shape the friendships’ texture—has therefore become a central question in developmental science.

To capture prosocial behavior in its full complexity, the researchers distinguished between altruism and concern for others. Altruism, in this framework, refers to voluntary, action-oriented helping: sharing resources, assisting a classmate in distress, or sacrificing one’s own time for another’s benefit. Concern for others, by contrast, captures the emotional, other-oriented side of prosociality—the empathic worry a child feels when a peer is sad or hurt, and the motivation to relieve that distress. This distinction echoes a broader movement in the field, championed by researchers such as Gustavo Carlo and Kristina Dunfield, to decompose prosocial behavior into subtypes such as helping, sharing, and comforting, each with its own developmental trajectory, motivational profile, and social consequences. Treating kindness as a monolith, the argument goes, obscures the very differences that matter most for prediction and intervention.

Methodologically, the study combined complementary sources of information about children’s social worlds. Altruistic behavior and emotional concern were assessed through self-report questionnaires, allowing children to describe their own tendencies toward helping and empathic worry. Mutual best friendships were identified using peer nominations, a technique in which children name the classmates they consider their best friends; a friendship counts as mutual only when both children name each other. This nomination approach is widely regarded as more objective than self-reported friendship alone, because it anchors the analysis in relationships that both parties recognize. The children who had mutual best friendships then reported on the quality of those friendships using dimensions drawn from established friendship quality measures, including companionship, help, closeness, emotional security, and conflict. Finally, all children completed a standardized measure of loneliness, adapted from the classic loneliness and social dissatisfaction scales developed by Steven Asher and colleagues in the 1980s.

The statistical strategy centered on multiple regression analyses, which allowed the researchers to estimate the unique contribution of altruism and concern for others to each friendship quality dimension and to loneliness, while controlling for the overlap between the two prosocial dimensions. The results were consistent for altruism: children who reported higher levels of altruistic behavior perceived their best friendships as higher in positive qualities across the board. Altruism predicted greater companionship, more help, deeper closeness, and stronger emotional security within the friendship. It also predicted lower levels of loneliness. In other words, the action-oriented helpers in the sample were not only enjoying richer friendships but were also less likely to feel socially isolated, suggesting that altruistic behavior functions as an active ingredient in building and maintaining rewarding peer bonds.

Concern for others told a more complicated story. As expected, emotional concern predicted greater emotional closeness in best friendships, lower levels of conflict, and reduced loneliness. These findings align with a substantial literature linking empathy to smoother conflict resolution and deeper relational intimacy; children who genuinely worry about a friend’s feelings may be better equipped to de-escalate disagreements and to provide the emotional attunement that close friendships require. But the analysis also produced one unexpected result: concern for others predicted lower companionship. Children high in empathic concern, that is, reported spending less time in the shared, activity-based side of friendship—the playing, hanging out, and doing-things-together dimension that companionship captures.

The authors interpret this counterintuitive pattern through the distinct functional roles the two prosocial dimensions may play. Altruism, being behaviorally oriented, may promote active engagement: the child who helps, shares, and steps in is visibly present in the flow of daily peer life, generating opportunities for joint activity and reciprocal support. Concern, being emotionally oriented, may contribute to depth rather than breadth—fostering intimacy and reducing relational strain, but not necessarily driving the frequency of shared activities. A child who feels deeply for others may invest in the emotional quality of a friendship without being the companion who organizes games or initiates playdates. The finding underscores that prosocial behavior is not a single dial that can be turned up uniformly; its dimensions pull friendship quality in partially different directions, and a complete account of children’s social development requires attending to both.

The loneliness findings deserve particular attention given growing concern about loneliness among young people worldwide. Meta-analytic work, including a 2021 synthesis by Tian and colleagues, has tracked trends in loneliness across decades of research on children and adolescents, and recent studies have explored how prosocial behavior relates to loneliness both directly and through social cognition. The present study adds a dimensional twist: both altruism and concern for others were associated with reduced loneliness, but apparently through partly different relational pathways—altruism through broad positive engagement across friendship qualities, and concern through closeness and low conflict. Loneliness in childhood is not simply the absence of peers; it is a subjective discrepancy between desired and achieved social connection. Children who actively help may find themselves more embedded in networks of mutual obligation and goodwill, while children who empathically attune to others may experience their existing relationships as more secure and less fraught.

The study also situates itself within a Greek educational and cultural context, which the authors treat as theoretically relevant rather than incidental. Greece has been described in prior literature as a relatively collectivist cultural setting, where family and in-group ties carry substantial weight, and the country’s prolonged socioeconomic crisis has been linked in epidemiological work to heightened mental health concerns among adolescents. Prior Greek studies, including work by Leontopoulou on altruism in Greek children and by Antonopoulou and colleagues on how primary school children perceive best friendships, provide local grounding for the present findings. Whether the differential effects of altruism and concern generalize across more individualist cultural contexts remains an open empirical question, but the cultural embedding of the study is a reminder that the meaning and expression of kindness are shaped by the social worlds in which children develop.

For practitioners, the implications are concrete. School-based social and emotional learning programs, whose effectiveness was reinforced by Durlak and colleagues’ influential 2011 meta-analysis, often target prosocial behavior as a unitary outcome. The new findings suggest that such programs might benefit from deliberately cultivating both action-oriented helping and empathic concern, since each appears to nourish different aspects of friendship—engagement and support on one hand, emotional depth and harmony on the other. Interventions that prompt acts of kindness, such as the kindness-counts experiments of Layous and colleagues, may boost peer acceptance; pairing those behavioral prompts with empathy training could, on this evidence, address the intimacy and conflict dimensions of friendship that kindness alone may not reach. The authors also caution that self-report measures of prosocial behavior are vulnerable to social desirability bias, a limitation the field has long acknowledged, and they note that the data are available from the corresponding author upon reasonable request given confidentiality constraints. The study received ethics approval from the Greek Ministry of Education and the Institute of Educational Policy, with written parental consent and child assent. As the authors conclude, conceptualizing prosocial behavior as a multidimensional construct is not an academic nicety—it is essential for understanding how kindness translates into the friendships that shelter children from loneliness.

Subject of Research: The role of altruism and concern for others in children's friendship quality and loneliness during middle childhood

Article Title: Understanding the Role of Prosocial Behavior in Children’s Peer Relationships: Implications for Friendship Quality and Loneliness

Article References: Vairami, M., Aivazidi, M., & Petrogiannis, K. (2025). Understanding the Role of Prosocial Behavior in Children’s Peer Relationships: Implications for Friendship Quality and Loneliness. Trends in Psychology. https://doi.org/10.1007/s43076-025-00497-1

Image Credits: AI Generated

DOI: 10.1007/s43076-025-00497-1

Keywords: prosocial behavior, altruism, concern for others, friendship quality, loneliness, middle childhood, peer relationships, peer nominations, social development, emotional well-being, Greece, developmental psychology