This study examined young children's behaviour predictions in direct reciprocal prosocial situations. Participants aged 4-6 years (N = 60) listened to four stories that addressed the actor's previous behaviour (prosocial/non-prosocial) combined with the partner's behaviour (prosocial/non-prosocial). Then, they made predictions regarding the actor's future behaviour. Children's predictions of a prosocial actor's behaviour were consistent with the tit-for-tat strategy. Regarding the behavioural predictions of the actor who had behaved non-prosocially, children did not predict that the actor would repeat non-prosocial behaviour, even if the partner did not behave prosocially. When the partner behaved prosocially, children predicted that the non-prosocial actor would behave prosocially the next time. Young children assumed that a partner's generous response could influence the future behaviour of the actor who had not behaved prosocially to behave prosocially the next time.