The present study aims to find the developmental path of event relation construction of Thai children. Data are narratives of Thai children in various age groups: preschool, kindergarten, elementary school, and adults, retrieved from the Thai Frog Story Corpus. The findings show constructions depicting both non-relation between events and event relations consisting of sequential, temporal, and causal relations. The three event relations found occur in different age groups. Sequential and temporal relations are constructed by all age groups, while causal relation occurs only in the groups of elementary school and adults. The levels of complexity among the three event relations and cognitive development are raised as the reasons of different ages in perceiving and constructing event relations.