One of the central goals of doctoral programs is to develop independent researchers and scholars who will lead the next generation of knowledge production. Despite extant evidence of inequalities in doctoral education, few studies have closely examined the experiences of first-generation college students who pursue a Ph.D. We examine how first-generation and continuing-generation doctoral students conceptualize the role of the faculty advisor/principal investigator (PI) in supporting their development as researchers. Our analysis of interviews from 111 first-year Ph.D. students in the biological sciences indicates that first-generation and continuing-generation students had similar overarching conceptions of PIs and the role of PIs in their development. However, the two groups ascribed different meanings to the same concepts. First-generation students expected more direct, skill-based guidance and assistance with learning to do research the "right" way. Conversely, continuing-generation students expected independence and support for their specific needs. We rely on Bourdieu's conceptualization of habitus to explain these differences and conclude by offering implications for advancing equity in doctoral education and supporting first-generation students, particularly regarding the alignment of student--advisor expectations.