In this study, we investigate whether emotional expressionsprovide cues to knowledge sufficient for predicting others’behavior based on their true and false beliefs. We adapted theclassic Sally-Anne task (Baron-Cohen, Leslie, & Frith, 1985)such that children (N = 62, mean: 5.58 years, range: 4.05-6.98years) were not told whether Sally saw Anne move the objector not. However, when Sally came back looking angry, evenfour-year-olds inferred that she had seen Anne move her toy;when she came back looking happy, children inferred that shehad not seen the transfer. Based on these inferences, five andsix-year-olds, although not four-year-olds, were able topredict where Sally would look for her toy.