Social origins are important predictors of adult success, and parental resources, particularly parental wealth, are positively correlated with adult well-being. Meanwhile, the overall population is now healthier and living longer than previous generations. Therefore, families are experiencing increased opportunities for multigenerational relationship formation and investment. This dissertation extends social mobility and stratification research by considering how multigenerational resources are related to young adult well-being. I examine how grandparents’ accumulated wealth prior to individuals’ eighteenth birthday is related to young adults’ educational attainment, self-rated general health and mental health, and financial independence. Additionally, in light of large, enduring racial wealth gaps between Black and White identified people, I examine whether and to what extent racially disparate patterns of family wealth accumulation condition the relationship between grandparent wealth and young adult well-being. I perform this investigation with analysis of the Panel Study of Income Dynamics (PSID) and the PSID’s Transition to Adulthood Study (TAS). I employ multivariate longitudinal analysis techniques to perform interracial and intra-racial analyses of the relationship between grandparent wealth and young adult well-being. I decompose racial group gaps to see whether the results are attributable to family socioeconomic characteristics or the return to those characteristics. Lastly, I use marginal probabilities to examine and compare the absolute and relative consequences of racially disparate levels of grandparent wealth across well-being outcomes.