In traditional Chinese culture, the family is the basic unit of society, while individuals are only one part of the family. The blood relationship between the father and son is the most important element of society. The extended families of old had "four generations living under one roof". The so-called "four generations under one roof" meant the cohabitation of the father and mother, son and daughter-in-law (or daughter and son-in-law), grandson and granddaughter-in-law, the great-grandson and the great-granddaughter. While modern families increasingly include only two generations living together, the tradition and the ideal of four generations living together still remains.