This study investigates the language learning experiences of a migrant child in an underprivileged migrant-marriage family in Japan through narrative inquiry. Data were collected over the course of a year through a migrant child survey, reflective journals and interviews with the migrant child and his mother, homeroom teacher and tutor to interpret the migrant child's narratives. Drawing on (Darvin, R., and B. Norton. 2015. "Identity and a Model of Investment in Applied Linguistics." "Annual Review of Applied Linguistics" 35: 36-56) investment model, the study reveals how and why the subject invested in "juku" (private tutoring) to bridge linguistic constraints and social barriers. The "juku" was regarded by the migrant child as a place to build connections and further expand his social network with "juku" classmates of a higher socioeconomic status in the hope of obtaining the economic capital necessary to overcome indigence. The findings from this study also show that emotions had a positive impact on the participant's identity development. This study has important implications pertaining to the lack of language learning opportunities among migrant children in Japan and the need for further studies on the language learning experiences that migrant children obtain through participation in supplementary tutoring.