Anthropomorphized animals are a prevalent character type in children’s books. However, stories with fantastical protagonists are associated with poorer social learning than those with human protagonists. We explored whether children’s representations of characters’ internal states and dialogue in story retells were related to story character realism (anthropomorphized animal, human), story theme (sharing, busyness), age, and vocabulary. Three- to seven-year-olds (N = 171) listened to one of four versions of an illustrated storybook that manipulated character realism and theme. Developmental trends were evident: Older children included more internal state references and dialogue in their retells than younger children. Of note, children retelling a prosocial story with human protagonists included more socio-relational language than those retelling a busy-themed story featuring humans; the same advantage was not evident for stories with animal protagonists. These findings imply that realistic protagonists may elicit more robust representations of social ideas in the minds of young children.