||The core of the presented bachelor thesis is to determine the effects of sibling's composition on child health quality. The first part of the thesis is focused on the microeconomic description of Model of Human Capital Investment, the Gender-Specific Model in particular. Also other findings and the health system of the examined countries are presented. In the second part, based on the findings from the theoretical model, three hypotheses are stated. Methodology is explained and econometric model is presented. How the gender, ratio of sisters and birth order affect health of children are subsequently tested for chosen Asian countries, namely, Bangladesh, India and Nepal. The last part is devoted to the description of empirical results and the occurred differences are discussed. The sibling's composition has shown to be an influential factor, mainly gender and ratio of sisters.