As robots and autonomous agents integrate into society, understanding their influence on human social dynamics is crucial. We investigate human-robot interactions, focusing on the impact of prosocial behavior by robots on subsequent human interactions and humans' willingness to exhibit prosocial behavior towards robots. Our study involved a token-collection game in a grid-world environment. Players, human or robot, could become trapped; a prosocial action involved another player freeing the trapped individual. Findings indicate that robots demonstrating prosocial behavior toward humans can inspire prosocial behavior toward others. Humans also show a notable propensity to assist robots. Witnessing robots engage in prosocial behavior may activate social norms related to cooperation, prompting humans to emulate these behaviors. Robots' actions could improve the saliency of these acts, focusing people's attention on prosocial behaviors they might not notice otherwise. Overall, the findings suggest that robots can promote prosocial behavior among humans, contributing to a more cooperative social environment. This research has implications for design and implementation of future autonomous systems, emphasizing the importance of social considerations in human-AI interaction studies.