The paper presents a model where the interplay between fertility, child labour and education can explain economic stagnation when parents live in an environment of high child mortality. If in contrast child mortality is low, the solution of the parental decision problem leads to perpetual economic growth. The two long-run states are connected by a path of demographic transition and economic take-off along which the incidence of child labour disappears. The paper also discusses alternative policies to escape from the low income equilibrium.