This article identifies a significant transformation in the role and identity of parents accompanying their child to clinic. This shift is a product of the intersection between paediatric and genetic medicine, where parents play a critical role in providing information about their child, family and ultimately, about themselves. To provide a context for this matrix, two broad areas of sociological inquiry are highlighted. The first is explanations of the role a parent plays in paediatric medicine and the second is the diagnostic process in paediatric genetics and the implications for parent and child identities. Drawing from an ethnographic study of clinical consultations, attention is paid to the changing role of parenthood and the extended role of patienthood in paediatric genetic medicine.