This study used a descriptive, phenomenological research approach. The problem for the study was: How do selected first-born adult participants describe their lived experiences of sibling interactions? Ten adults between the ages of 40 and 50 years who each had only one sibling were the study sample. A researcher-developed interview guide was used to conduct semi-structured interview, which were tape-recorded.

Data were analyzed by using a methodology suggested by Colaizzi. From the transcripts the researcher extracted significant statements, meanings of these statements were formulated, common themes were allowed to emerge, descriptive statements were composed, and finally the fundamental structure of the phenomenon was presented.

The study was guided by a theoretical framework on sibling interactions proposed by Schvaneveldt and Ihinger. Five of their 22 propositions were specified as being of major concern. Data were analyzed in order to find or fail to find support for the 22 propositions.

Findings of the study included the emergence of 18 common themes. From the literature review, themes that were anticipated included: initial response to sibling, siblings as playmates, parental discipline, favoritism, conflict, sibling response to academic comparison, sibling influence, family coalitions, family peacemakers, compliant sibling, desire to trade positions with sibling, pioneer role, and jealousy.

Themes which were not expected, but which emerged included: responsibility to which parent, sibling's concern for participant, and explanation for lack of closeness. A theme which was expected but did not emerge from these participants was "dethronement.".

The conclusions of the study were that the data gave support for the five propositions specified as major concerns. For six propositions, the data did not yield any evidence regarding support. There was also some support for the remaining 11 propositions. The theoretical framework offered value for nursing. Recommendations were made for further research.