This study examined the effect of mortality change on the probabilities of survival for various family members and parent/child joint life expectation in Chinese mainland and Taiwan during the past 60 years. Major increases in life expectancy have led to the doubling of the average number of person years of an individual's life spent as a grandparent during that time. In a sense, the family burden of old age support is twice as much as before. It is concluded that the role of family in providing old age support needs to be complemented and reinforced by public programs.