The study investigates the relationship between positive emotions, ego-resilience, and life satisfaction. It tests the broaden-and-build theory, which posits that positive emotions help build lasting resources that enhance life satisfaction. The study used diary data from 86 students over one month to measure daily emotions, ego-resilience, and life satisfaction. Results show that positive emotions predicted increases in both ego-resilience and life satisfaction, while negative emotions had weak or no effects. Positive emotions mediated the relationship between baseline and final resilience, but not life satisfaction. The findings suggest that momentary positive emotions, rather than general life satisfaction, are crucial for linking happiness to desirable life outcomes. The study also found that changes in resilience mediated the relationship between positive emotions and increased life satisfaction, indicating that happy people become more satisfied as they develop resources for living well.The study investigates the relationship between positive emotions, ego-resilience, and life satisfaction. It tests the broaden-and-build theory, which posits that positive emotions help build lasting resources that enhance life satisfaction. The study used diary data from 86 students over one month to measure daily emotions, ego-resilience, and life satisfaction. Results show that positive emotions predicted increases in both ego-resilience and life satisfaction, while negative emotions had weak or no effects. Positive emotions mediated the relationship between baseline and final resilience, but not life satisfaction. The findings suggest that momentary positive emotions, rather than general life satisfaction, are crucial for linking happiness to desirable life outcomes. The study also found that changes in resilience mediated the relationship between positive emotions and increased life satisfaction, indicating that happy people become more satisfied as they develop resources for living well.