["Developmental Science, Volume 29, Issue 3, May 2026. ", "\nABSTRACT\n\nUnited Nations SDG 10 focuses on reducing inequalities in civil society. To address the emergence of attitudes and reasoning about social exclusion based on wealth and ethnicity, Chinese Singaporean children's predictions about peer group inclusion decisions based on ethnicity (Chinese/Indian) and wealth (high/low) were investigated. A cohort of 103 participants (4–7 years, Mage = 5.79; 49% female) was asked to predict and reason about how a peer group would make choices about including a new peer over three conditions. In the Ethnicity condition, participants expected peers to give priority to same‐ethnicity friendships; this expectation increased with age. In the Wealth condition, participants’ expectations for peers to give priority to same‐wealth friendships increased with age. When both ethnicity and wealth were independently manipulated, participants expected their peers to give priority to high wealth, even if that meant the group would be cross‐ethnic. Children referenced access to material resources and opportunities when reasoning about why low‐wealth and high‐wealth groups would choose to include a high‐wealth peer. In same‐wealth contexts, shared identity between the peer and group was also referenced. Participants used moral reasoning to explain their expectations for the low‐wealth Chinese group's choice of a high‐wealth Chinese peer; this reasoning was not evidenced when Chinese participants predicted a low‐wealth Indian group's choice for including a high‐wealth Indian peer. These novel findings revealed children's nuanced expectations about exclusionary peer group norms regarding wealth and ethnicity. Reducing exclusionary attitudes early in life contributes to sustainable development across cultural contexts.\n\n\nSummary\n\nYoung Chinese Singaporean children expected peer groups to include high‐wealth peers, though older children increasingly predicted low‐wealth groups would include peers of the same wealth.\nChildren expected groups to prioritize high wealth over shared ethnicity when both traits were presented simultaneously.\nChildren reasoned that groups include high‐wealth peers due to access to material resources and, at times, shared group identity.\nMoral reasoning emerged when children predicted that low‐wealth Chinese, but not Indian, groups would include high‐wealth peers for resource‐sharing purposes.\n\n\n"]