Traditionally in Korea, the typical family size is quite large, with three or four generations usually living together under the same roof. Because infant mortality was high and a big family was thought of as a blessing, having many children was the desired option. However, as the country underwent rapid industrialization and urbanization during the 1960s and 1970s the pattern was accompanied by an effective birth control drive, and the average number of children in a family dramatically decreased to two or less in the 1980s.
Having a long Confucian tradition under which the eldest son takes over as head of the family, many Korean families preferred having a son. To tackle the problem of male preference, the government has completely rewritten family-related laws in a way that ensures equality for sons and daughters in terms of inheritance.
Industrialization of the country has made life more hectic and complicated. Young married couples have begun to separate from their extended families and start their own homes. Now almost all families are couple-centered nuclear families.