This study investigated the degree to which a family investment model would help account for the association between family of origin socioeconomic characteristics and the later educational attainment of 451 young adults (age 26) from two-parent families. Parents' educational level, occupational prestige, and family income in 1989 each had a statistically significant direct relationship with youths' educational attainment in 2002. Consistent with the theoretical model guiding the study, parents' educational level and family income also demonstrated statistically significant indirect effects on later educational attainment through their associations with growth trajectories for supportive parenting, sibling relations, and adolescent academic engagement. Supportive parenting and sibling relations were linked to later educational attainment through their association with adolescent academic engagement. Academic engagement during adolescence was associated with educational attainment in young adulthood. These basic processes operated similarly regardless of youths' gender, target youths' age relative to a near-age sibling, gender composition of the sibling dyad, or gender of parent.Keywords educational attainment; academic engagement; parenting; sibling relations; SES Substantial evidence indicates that the number of years of formal schooling completed by early adulthood is associated with young adults' initial labor market status and income (Bjarnason, Correspondence regarding this article should be addressed to Janet N. Melby, Institute for Social and Behavioral Research, Iowa State University, 2625 North Loop Drive, Suite 500, Ames, IA 50010-8615. Electronic mail may be sent via Internet to jmelby@iastate.edu. Publisher's Disclaimer: The following manuscript is the final accepted manuscript. It has not been subjected to the final copyediting, fact-checking, and proofreading required for formal publication. It is not the definitive, publisher-authenticated version. The American Psychological Association and its Council of Editors disclaim any responsibility or liabilities for errors or omissions of this manuscript version, any version derived from this manuscript by NIH, or other third parties. The published version is available at www.apa.org/journals/dev. (Blau & O. D. Duncan, 1967;Chand, Crider, & Willits, 1983), and life satisfaction and healthy aging in general (Meeks & Murrell, 2001). Prior research identifies relationships between youth educational outcomes and family of origin characteristics such as parental support and family income (e.g., Best, Hauser, & Allen, 1997; Brooks-Gunn, G. J. Furstenberg, Eccles, Elder, Cook, & Sameroff, 1999; Melby & R. D. Conger, 1996;Sieben & DeGraaf, 2003). Recent literature also suggests that siblings may be associated with youth educational outcomes (G. J. Duncan, Boisjoly, & Harris, 2001). Less is known, however, about the combined effects of these family factors on educational attainment (Connell & Halpern-Felsher, 1997). Moreover, despite considerable evid...
