This paper examines the effect of birth order on educational attainment and child labour in Lesotho. Using family fixed effects models, I find robust negative birth order effects on educational attainment and child labour. The birth order effects on educational attainment are in sharp contrast with the evidence from many other developing countries such as Ecuador and Kenya, but are consistent with the evidence from developed countries. I further find that these birth order effects are pronounced in large families, and families with first-born girls, which suggests presence of girls' education bias. Turning to potential pathways of these effects, I find that they are not propagated through family wealth, but mainly through birth-spacing. These results are robust to different sample restrictions.