Research Findings: Few studies have examined second-born preschool children's empathy development under China's universal two-child policy. The purpose of this study was to explore the differences in empathy between Chinese preschool children with one older sibling and without siblings. A total of 180 children were purposively sampled from 14 preschools in Beijing to participate in the study, including 90 only children and 90 second-born children. We conducted tasks with children individually to assess their emotional empathy. The results suggest that second-born children exhibited higher levels of empathy than only children after controlling for demographic characteristics. Specifically, empathy of second-born children was significantly higher than that of only children in response to three emotions (i.e., sadness, fear, and anger). Practice or Policy: This study highlights the benefit of growing up with siblings. Interactions and relationships with siblings can enhance children's empathy. We should provide more opportunities and intentional instructions for only children to interact with and get along with peers.