Some outcomes are brought about by intentional agents with access to information and others are not. Children use a variety of cues to infer the causes of outcomes, such as statistical reasoning (e.g., the probability of the outcome) and theory of mind (e.g., a person's perceptual access, preferences, or knowledge). Here we show that children use these cues to infer cheating, a finding which informs our understanding of the flexibility of children's theory of mind. In four experiments (N = 444), 4‐ to 7‐year‐olds saw vignettes about blindfolded agents retrieving 10 gumballs from a distribution of yummy and yucky gumballs. Children were then asked if agents were really blindfolded or had peeked. We manipulated the probability of the outcome (i.e., the correspondence between the distribution sampled from and the outcome produced) and the ordering of the outcome was patterned (e.g., five yummy then five yucky) or haphazard. From age 5, children began to use both cues to infer cheating, and also showed signs of flexibly integrating these cues. Together, these findings show that young children can detect cheaters, and that their theory of mind reasoning is flexible and not based on simple and rigid rules (e.g., equating not‐seeing with failure). The findings also suggest that children use probabilistic reasoning to infer knowledge.