Pediatric clinical research in low-resourced countries involves individuals defined as "vulnerable" in research ethics guidance. Insights from research participants can strengthen the design and oversight of studies. We share family members' perspectives and experiences of an observational clinical study conducted in one Kenyan hospital as part of an integrated empirical ethics study. Employing qualitative methods, we explored how research encounters featured in family members' care-seeking journeys. Our data reveals that children's vulnerability is intricately interwoven with that of their families, and that research processes and procedures can inadvertently add to hidden burdens for families. In research, the potential for layered and intersecting situational and structural vulnerability should be considered, and participants' agency in constrained research contexts actively recognized and protected.