Multi-informant designs are increasingly recognised as essential for capturing the complexity of children’s developmental contexts, but analytic approaches to such data vary widely, with important consequences for how different perspectives are understood. In the context of 134 two-child families in eastern China, this seminar uses sibling relationship quality as a case example, drawing on reports from caregivers and first-borns through quantitative questionnaires, and from preschool second-borns through age-appropriate qualitative interviews. Caregivers can arguably provide an outsider’s more detached view on sibling relationship, whereas children themselves as active participants in sibling interactions can share an insider’s subjective interpretations, making a multi-informant approach particularly informative. Exploratory structural equation modelling, multi-trait multimethod analyses, and latent profile comparisons were applied to assess both shared and divergent perspectives. Preliminary findings show systematic differences across informants, with caregivers tending to emphasise sibling conflict, whilst children highlight more positive relational qualities. The seminar concludes with a reflection on what different approaches to triangulation imply for the interpretation of sibling relationship data and, more generally, for the design and analysis of multi-informant studies in quantitative research.
