Friendship is more than strategic reciprocity: Preschoolers' selective sharing with friends cannot be reduced to strategic concerns.

The current study investigated whether children share especially much with their friends when sharing can be reciprocated (strategic sharing) or whether friendship and strategic reciprocity are independent factors in predicting children's sharing. If the former is the case, children should prefer their friend relatively more in a situation where the friend can reciprocate than in a situation without the possibility for reciprocity. In two experiments, 3- and 5-year-old participants (N = 270) could distribute stickers between themselves and three recipients: a friend, a child who would join the kindergarten group the next day, and a stranger. Half of the children were led to believe that their generosity could be reciprocated, and the other half were not. In Experiment 1, this was implemented by anonymous and nonanonymous sharing. In Experiment 2, the possibility of reciprocity or lack thereof was explicitly mentioned. The results show that participants across both age groups shared more resources with their friend than with less familiar recipients. Potential reciprocity affected 5-year-olds' sharing but not 3-year-olds' sharing-but only if reciprocity was explicitly mentioned (Experiment 2). Importantly, the preference for the friend was independent of the possibility to be reciprocated for all children. The current study shows that friendship and strategic reciprocity are relevant but probably largely independent factors for children's sharing. That is, the preference to share with friends cannot be reduced to strategic considerations.