A deep understanding of any phenomenon requires knowing how its causal elements are related to one another. Here, we examine whether children treat causal structure as a metric for assessing similarity across superficially distinct events. In two experiments, we presented 156 4-7-year-olds (approximately 55% of participants identified as White, 29% as multiracial, and 12% as Asian) with three-variable narratives in which story events unfold according to a causal chain or a common effect structure. We then asked children to make judgments about which stories are the most similar. In Experiment 1, we presented all events in the context of simple, illustrated stories. In Experiment 2, we removed all low-level linguistic cues that may have supported children's similarity judgments in Experiment 1 and used animated videos to support understanding of the causal elements in each story. Results indicated a gradual shift between 4 and 7 years in children's use of causal structure as a metric of similarity between narratives: While we found that children as young as five were capable of correctly representing the causal structure of each story individually, only 6- and 7-year-olds relied on shared causal structure across stories when making similarity judgments. We discuss these findings in light of children's developing causal and abstract reasoning and propose directions for future work. (PsycInfo Database Record (c) 2024 APA, all rights reserved).