This multiple case study examined Mexican mothers' beliefs on social and moral development in light of their adaptation to the United States. Super and Harkness' (1986, 2002) ecocultural framework and more specifically, the concept of the developmental niche, guided the analysis. Participants were five Mexican immigrant mothers living in the Phoenix metropolitan area with children between three and four years old. Using participant observation, mothers were shadowed during the day for a period of nine months and were interviewed four times. Additionally, a Q-sort activity on cultural values and a vignette activity were conducted. Evidence of continuity in the importance given to traditional beliefs such as being "bien educado" (proper demeanor) and showing "respeto" (respect) was found. However, the continuity on the teaching of cultural values was accompanied by changes in beliefs and practices. The traditional construct of a "chipil child" (a needy, whiny child) was connected to the idea that mothers somehow need to restrict how much affection, time and gifts they give to their children. This concern was in turn related to the higher access to consumption goods in the United States. It is argued that acculturation is lived differently by mothers, according to their educational attainment, use of expert advice and contact and knowledge with American mainstream culture.