- Decisions about college are significant in the lives of students and their families, especially since these are often the first major life-decisions that adolescents are able to make largely on their own (Galotti, 1995; Galotti & Mark, 1994). It is widely recognized that family history plays a role in whether a person chooses to pursue post-secondary education, with children of parents that hold college degrees far more likely to follow in their footsteps. Little is known, though, of other family relationships and their impacts on educational decisions. Sibling relationships have been identified as playing a large role in development during childhood and adolescence, with siblings acting as role models, supporters, collaborators, and competitors, among other things (Cicirelli, 1995; Milevsky, 2005; Seginer, 1998; Weaver, Coleman, & Ganong, 2003). Positive sibling relationships have been associated with child adjustment (Pike, Coldwell, & Dunn, 2005), while conflictual relationships between siblings can help adolescents learn about social rules and boundaries (Raffaelli, 1992). In young adulthood, siblings spend less time with one another but are more likely to report emotional and warm relationships along with a decrease in conflict (Buhrmester & Furman, 1990; Scharf, Shulman, & Avigad-Spitz, 2005). The quality of the relationship between siblings has also been found to be critical since these relationships play a role in individuals’ psychosocial and emotional development. Positive sibling relationships are related to positive sibling adjustment, and positive and affectionate relationships can be protective in the face of stressful situations (Branje, van Lieshout, van Aken, & Haselager, 2004; Gass, Jenkins, & Dunn, 2007; Pike et al., 2005; Senginer, 1998). This thesis is grounded in the life course theoretical perspective. The life course perspective provides many conceptual ideas that are promising for understanding the role siblings may play in first-generation students’ decision-making process around college. Specifically, the main life course principles of historical time and place, linked lives, timing in the life, and agency are considered, along with institutionalization of the life course and cumulative advantage and disadvantage.This exploratory study examines sibling and parent relationships as they relate to college decision-making for first-generation college students. First-generation college students are defined as those whose parents never enrolled in college or those whose parents never graduated from college (Cabrera, 2014; Nunez & Cuccaro-Alamin, 1998; TRIO History; TRiO Student Support Services, 2016). Of particular interest for this study is whether the quality of sibling relationships impacts first-generation students, and if their influence is greater than the influence of their parents. Measures used in the study include a variation of the Warmth scale from the Adult Sibling Relationship Questionnaire-Short (Stocker, Lanthier, & Furman, 1997; Lanthier, Stocker, & Furman, 2000), parent and sibling college decision-making matrices, and open-ended questions pertaining to whether and how siblings and parents impacted college decisions. Research questions posed for this study are as follows: 1. Who contributes more in the college decision-making process, parents or siblings? 2. Is sibling warmth associated with college decision-making above and beyond demographic factors, first-generation status, and whether or not siblings have attended college? 3. Do siblings provide more assistance in the college decision-making process among first-generation students than among non-first-generation students? 4. Among first-gen students, are the roles of siblings and parents less differentiated in the college decision-making process?Results from this study indicated that siblings and parents contribute a significantly different level of assistance in the college decision-making process of students, with parents contributing a significantly larger amount (as indicated by the number of pre-college activities that parents participated in compared to siblings). Sibling warmth was found to be significantly associated with college decision-making, above and beyond demographics, first-generation status, and siblings’ college attendance. For first-generation students, siblings did not contribute a higher level of assistance in the college decision-making process when compared to their non-first-generation counterparts. Finally, it was found that while parents play a larger role than siblings in the college decision-making process of students, the difference in support between parents and siblings is far less distinct when the student is first-generation.This research provides insight into how sibling warmth and college attendance of siblings can play a role in the college aspirations of others in the family. It also highlights the importance of siblings specifically for first-generation students, indicating that while parents remain a significant source of support, siblings in these situations can be a critical supplementary resource.