Background: A local perspective on diarrheal illness has been shown to enhance control strategies for diarrheal disease in traditional rural settings. We aimed to assess caregivers’ understandings of childhood general and diarrheal illness, in one rural community in Vanuatu, to help formulate control strategies for preventing diarrheal disease. Findings: This was a descriptive study using qualitative analysis of responses to open-ended questions to provide a fuller understanding of illness. Thematic analysis with categories derived from medical anthropology was used to analyse responses and draw conclusions. Twenty-nine participants were interviewed; 22 were maternal responses, three were traditional practitioners, two were rural health care workers, one was a spiritual healer and one had a caregiver role. Respondents categorised illness as biomedical or traditional. Explanations of illness were enmeshed in and derived from both the traditional and biomedical system as the illness experience in the child under their care unfolded. Diarrheal severity influenced treatment selection and respondents expressed a preference for biomedical assistance. Respondents articulated a preference for biomedicine as the primary help-seeking resort for small children. Exclusive reliance on either traditional or biomedical options was uncommon. Local herbal remedies were the preferred home treatment when illness was known or mild, while oral rehydration therapy was used when accessing biomedical practitioners. Conclusions: Belief about diarrheal illness was influenced by traditional medicine and biomedicine. New evidence points to a growing preference for biomedicine as the first choice for severe childhood diarrheal illness. Diarrheal illness could be countered by maternal hand hygiene education at the medical dispensary and rural aid post.