How birth order moderates the negative effects of insecure attachment on anticipatory anxiety regarding parent care

Caregiving for aging parents can be a stressful process for middle-aged adults. Accordingly, many adult children experience anticipatory anxiety regarding care for their parents (i.e., filial anxiety), which can lead to health problems. Previous studies indicated that parental attachment is a crucial determinant of filial anxiety. However, in primogeniture cultures, in which first-born children inherit all the family property, the birth order of adult children directly influences caregiving for parents. Therefore, the present study aimed to examine the moderating effect of birth order between insecure attachment and filial anxiety. In total, 515 middle-aged Japanese adults (21.7% men) with a mean age of 32.27 (SD = 5.34) years completed an online questionnaire. Parental attachment was assessed with the Experiences in Close Relationship-Relationship Structure Scale, while filial anxiety was assessed with a single item. We conducted multiple regression analyses separately for filial anxiety regarding care for mothers and fathers. The negative effect of attachment avoidance on anxiety regarding care for mothers was stronger in adult children who were born first, and that of attachment anxiety was stronger in adult children who were born later. High attachment avoidance increased anxiety regarding care for fathers, regardless of birth order. Birth order played a major role in determining filial anxiety, especially for mothers. These results are thought to reflect the Japanese cultural conventions of caregiving. This study has valuable implications for understanding filial anxiety from a culture-specific perspective.