Some children who bully others are also victimized themselves (“bully‐victims”) whereas others are not victimized themselves (“bullies”). These subgroups have been shown to differ in their social functioning as early as in kindergarten. What is less clear are the motives that underlie the bullying behavior of young bullies and bully‐victims. The present study examined whether bullies have proactive motives for aggression and anticipate to feel happy after victimizing others, whereas bully‐victims have reactive motives for aggression, poor theory of mind skills, and attribute hostile intent to others. This “distinct processes hypothesis” was contrasted with the “shared processes hypothesis,” predicting that bullies and bully‐victims do not differ on these psychological processes. Children (n = 283, age 4–9) were classified as bully, bully‐victim, or noninvolved using peer‐nominations. Theory of mind, hostile intent attributions, and happy victimizer emotions were assessed using standard vignettes and false‐belief tasks; reactive and proactive motives were assessed using teacher‐reports. We tested our hypotheses using Bayesian model selection, enabling us to directly compare the distinct processes model (predicting that bullies and bully‐victims deviate from noninvolved children on different psychological processes) against the shared processes model (predicting that bullies and bully‐victims deviate from noninvolved children on all psychological processes alike). Overall, the shared processes model received more support than the distinct processes model. These results suggest that in early childhood, bullies and bully‐victims have shared, rather than distinct psychological processes underlying their bullying behavior.