Children's tendency to prefer rich to poor people and to view wealthy individuals more positively has been well-documented, but little is known about (a) the mechanisms underlying this "pro-wealth" bias and (b) the extent to which it holds across various social domains (e.g., friendships vs. school project partners). Using a mixed-methods approach, we examined the development of status-based social preferences in a socioeconomically diverse sample of children from Chinese American immigrant families (N = 169; 7-11 years; MAge = 9.16 years, SD ± 1.05; 87 male, 82 female). We examined the development of these preferences in middle childhood, a period during which aspects of group membership and social stratification are salient, particularly for children of immigrants. Children exhibited preferences for a high-status child over a low-status child across three social domains (friendship, playdate, and school project). Children's open-ended responses explaining their preferences most commonly referenced status-based stereotypes (e.g., "He's more educated, he might know more about the topic") and personal loss or gain (e.g., "I'll get to play with his stuff"). Children higher in parent-rated effortful control exhibited fewer status-based preferences and were less likely to reference status-based stereotypes and personal loss or gain in their explanations. Together, these findings shed light on the complexity and nuance of children's pro-wealth bias, as well as the underlying forces that drive these social preferences. (PsycInfo Database Record (c) 2024 APA, all rights reserved).