Adult participants play a pivotal role in doctor-parent-child interactions at the general practitioner's (GP's) surgery. The child's opportunities to participate are rather limited and parental speaking for the child is, in a way, institutionally co-constructed. This study aimed at further characterizing the relationships within this triad by developing a typology of doctor-parent-child interactions, which classified adult behavior in terms of supporting versus non-supporting child participation. The child's participation was described in terms of display of involvement and turning for support. Analyses of 105 videos show that in most consultations, both GP and parent displayed non-supportive behavior. Despite the GPs' initial efforts to involve the child in the interaction, 90% of the consultations ended up in a non-participatory way. During this last segment of diagnosis and treatment information, the child's voice was hardly heard, as reflected in the minimal involvement displayed and the absence of turning to the parent for support. It is concluded that the bi-directional perspective chosen in this analysis allowed for a better understanding of the underlying mechanisms leading to the stereotypical picture in both literature and actual practice of triadic medical interactions being dominated by both adult participants. The low degree of child participation should not solely be seen as a consequence of adult behavior, but rather as a co-construction of all three participants. The results are discussed from a pedagogical perspective, and implications for medical practice are formulated.