Understanding children is important in the Early Childhood Education and Care (ECEC) practice. The ECEC conference is an opportunity for practitioners to deepen their understanding of children. This research focuses on the Trajectory Equifinality Model (TEM), which is the methodology of qualitative research as a tool promoting a practitioner's understanding of children in the ECEC conference. The features of the TEM are modeling the process of a research participant's experience and imagining and considering the possibilities ("ifs") of a different experience from just the facts. This research clarifies the meaning of these features of the TEM for the practitioner's understanding of children. The ECEC conference use of the TEM was tried, and the conversation of the practitioners there was analyzed. As a result, it was revealed that two developments of understanding children was brought to the practitioners by discussing the experience and the "ifs" of the target child. First, the practitioners can obtain a reasonable understanding of the cases and the children by comparing the facts and the "ifs." Second, the practitioners can discover a child's potential capabilities and demands by imagining the figure of a child's "ifs." Therefore, the ECEC conference using the TEM supports the practitioners catching a child's state and intentionality and planning a suitable assistance.