The current study examined the trajectory of gender role attitudes of 471 Mexican-origin adolescents (236 girls, 235 boys) from 5th grade (M[subscript age] = 10.86 years) to 11th grade (M[subscript age] = 16.75 years), investigating how situating identities (i.e., gender, nativity, SES), ethnic identity (i.e., ethnic pride), and familial context (i.e., parents' attitudes) contributed to adolescents' gender role attitudes across time. Participant interviews were conducted every other year, resulting in 4 waves of data. Most parents (96%) were Mexico natives, with an average immigration age of 18.16 years for fathers and 14.01 years for mothers. Results revealed linear and quadratic trends in gender attitude traditionality for all adolescents, characterized by a linear decline through age 16 years that leveled off through age 18 years. Although both girls and boys trended toward egalitarian gender role attitudes across adolescence, girls endorsed more egalitarian attitudes than did boys. Adolescents from higher-SES backgrounds endorsed more egalitarian attitudes than those from lower-SES backgrounds. Significant within-person effects of ethnic pride surfaced, such that children with higher levels of ethnic pride at any given time also reported more traditional gender role attitudes. Significant between-person effects of mothers' and fathers' attitudes were found, such that parents with more traditional gender role attitudes tended to have children with relatively more traditional gender role attitudes. Overall, these findings highlight the importance of studying gender development in conjunction with situating identities, cultural identities, and the broader context, particularly when children are embedded in multiple cultures with contrasting gender role expectations.