In modern society, the younger generation needs to develop parental readiness. The purpose of this study was to investigate the younger generation's developmental process of Sympathetic Responsiveness (SR) to children regarded as an important aptitude for parenting. In addition, this research identified the educational factors: knowledge of child development, experience in early childhood education and care, and individual or family factors; affinity with one's own parents, acceptance of becoming parents, all of which would affect SR and the relationships between their SR and these factors were examined. Each specific scale was developed and the questionnaires used by each scale were administered to 500 junior high school students, 537 senior high school students, and 574 university students. It was found that SR develops as their grades get higher. Although male students' SR is at a lower level of development than female SR, such differences between males and females become smaller as their grades get higher at least in the case of university students. Furthermore, the analyses on the relationships between their SR and the effective factors revealed that the amount of knowledge of child development and the level of acceptance of becoming parents were significantly associated with their SR. In university students, it was shown that experience in early childhood education and care was related to their SR.