This article addresses findings about knowing rather than assuming dialogical interactions between children. Understanding the nature of relation indicates the form of children's interaction within participatory pedagogy. During a Dialogical Approach to Observation two-year-old children, their parents and key person practitioners also enact participation together. The approach is based on Buber's relational ontology of dialogue between 'I and You'. Through interpreting the perceived attitude or regard for the other, the children are found to engage in openness before entering into mutuality in interactions, or not. There is evidence of dialogical agency in their decisions to enter dialogue and regard others as relevant. The extension of dialogue is found, beyond human interaction, to encompass materials and the environment itself. The interpretations have significance for the understanding of potential dialogical relations and for future engagement in dialogical participatory pedagogy.