Fertility transition of ethnic minorities is an integral part of the demographic transition of China. Studying fertility transition among different ethnic groups offers a new perspective in understanding fertility transition in China. This study uses multiple waves of micro census to describe fertility transitions of different ethnic minority groups. Utilizing multilevel models, this study also identifies the between and within group determinants of ethnic minority fertility behaviors. Results show that similar to Han Chinese, ethnic minorities also experienced fertility decline over the past forty decades. Yet their rates of decline were modest. Most ethnic minority groups reached near replacementlevel fertility since 2000, and some saw modest increase in the recent decade. There exist heterogeneities within ethnic groups. Different ethnic groups exhibit different fertility patterns. The multilevel analysis results show that ethnicspecific traits had diminishing yet still significant impact on fertility behaviors. Within ethnic group differences account for a larger part of the total fertility variations.

China is experiencing rapid population ageing and witnesses a wide spread of information technology. The rise of novel internet technologies may increasingly influence older adults' daily life. Using data from a survey on midage and older adults' short video application use conducted in 2021, this study investigates the relationships between short video app usage and midage and older adults' social networks, commutation with family members and friends, social inclusion and mental health. Results show that the moderate use of short video app increases midage and older adults' communication with families and friends, expands their social networks, and promotes their social inclusion. We should also acknowledge that older people face many problems and risks in the digital era. Findings suggest that collective efforts should be made by government, corporations, local communities as well as families to mitigate agerelated digital divide.