Language-related attitudinal differences between two bilingual students at the University of Texas at El Paso are examined. The student designated "R" is found to exhibit language loyalty to both English and Spanish. Spanish is his language of choice chiefly when his conversational partner expects Spanish. Student "L" maintains preferential loyalty to Spanish, which he uses invariably with all Mexican- Americans. R and L were raised in similar families, schooled in apparently identical environments, and live in the same neighborhood. Standard sociolinguistic questionnaires provide no explanation for the attitudinal differences between the two. Closer examination of the students' background leads to the conclusion that the differences stem from two factors. First, though both students' mothers are virtually Spanish monolingual, R's mother left her middle-class Mexican home in her twenties, after receiving a high school education, while L's mother left her working-class home in her teens, after receiving an eighth-grade education. Second, L, unlike R, spent his first eleven years and received his elementary education in El Paso's Segundo Barrio, a slum district. These findings imply that portraits of one's subjects, based on close personal acquaintance, can be a more effective research tool than standardized questionnaires. (JB)