This study explored child behaviours that enable mothers to perceive their child's minds. We administered the Mind Perception Questionnaire to 216 women with children aged between 0 and 24 months and 221 working women without children. Participants responded with mind perceptions for various entities, including for their children (a 0--2-year-old child). Further, to examine child-related behaviours that may influence mothers' perceptions of their children's minds, we asked them about which actions made them perceive what their babies had in mind. We found that mothers perceived their children as having minds similar to their own while working women without children perceived 0--2-year-old children as being different from themselves. Mothers' perceptions of their children's minds were associated with child-related behaviours that made communication possible. Thus, this study was able to identify important milestones of child development, by examining the mother's point of view regarding their children's minds.