On what conditions are elder siblings recognized as family members and under what condition is the consciousness sustained

This paper will discuss the recognition and consciousness by which we could win acceptance as family members and what conditions should sustain (keep up) that consciousness. The discussion uses the 1998 data of the Japanese National Family Research (NFR98) to discuss these conditions. The logic analysis which will explain the conditions under which one recognizes an elder sibling as his/her family member or not shows that the frequency of their contact with each other is the primary factor and his/her marital status is also effective. The frequency of their contact with each other is more effective among women. The marital status is significantly effective only among young and middle age cohorts, but not among elder age cohorts.