The Marxist understanding of the Family focuses on its role in the process of production. According to Engels, whose 'The Origins of the Family' is a major source for Marxist sociologists of kinship, the Family institutes a division of labour, whereby the male proletarian sells his labour to earn a wage to provide for other family members, whilst the wife maintains the home with domestic labour and looks after the children. Later Marxist Feminist theorists have referred to this as 'social reproduction'. The Family also secures a means for the accumulation of wealth among the bourgeoisie, via the use of women's reproductive capacities to hand down wealth over generations from father to son. Marxists thus understand the Family as a site not only of labour and of capital, but therefore of exploitation.