Diverging destinies: How children are faring under demographic transition

India reached the replacement level of fertility in 2020. However, the journey of fertility transition is unconventional and heterogeneous within the country and across the different socio-economic groups. The fertility transition is considered to be faster than its socio-economic and health transition in several states. Thus, it has been presumed that the returns to fertility decline are heterogeneous across the states and population sub-groups. Our specific hypothesis is that although rich and poor, and educated and un-educated, everyone had significantly contributed to the fertility decline in response to family planning policies, only those socio-economically better-off have been investing relatively more in their children compared to the poor, and this has led to diverging destinies for children. We tested this supposition using a macro-level panel dataset (1992–2021), fixed and random effects, and IV regression models. The results confirm that child health care and outcomes have diverged while fertility declined from 1992 to 2021. These results are sustained in multiple robustness checks. While fertility is declining with highly state-sponsored family planning programmes, the persistent socio-economic inequalities are leading to unequal progress in health outcomes for children in India.