Does the number of siblings affect adult income? An indonesian case study

This study examines the effect of family size in childhood on the level of welfare achieved in adulthood. We used the Mincer earnings function, a multiple linear ordinary least squares (OLS) regression model with the logarithm of income as a dependent variable. The results show that the number of siblings does not have a significant direct impact on income. However, it has a significant, indirect, and negative impact on education, which in turn has a significant positive impact on income. A smaller family size with fewer siblings is a favorable option for parents who want to maximize human capital development, higher income levels, and higher welfare for their children in the future. Because such research is rare in developing countries like Indonesia, the study contributes to our understanding of the relationship between the number of siblings in childhood and the income level in adulthood.