There is a study that investigated the effects of family wealth - using the agricultural land size as a proxy - on the probability that a child works in rural areas of Brazil. The results indicated that, after controlling for individual and family characteristics (age, gender, education and race), and demographic and regional effects, child labor was affected by family wealth. It was possible to observe that the child's probability to work as a function of the land size followed a parabolic curve, showing that as the land size increased, increased the probability that a child worked up to a maximum of 76 hectares, after which child labor decreased.
Trabalho infantil no meio rural brasileiro: Evidências sobre o "paradoxo da riqueza". Economia Aplicada. 2010. Ana Lucia Kassouf and Marcelo Justus
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Prof. Ana Lucia Kassouf