Previous research reveals that the characteristics and practices of a child's family are important determinants of its chances of surviving beyond childhood. This study investigates the effects of consanguinity on a family's odds of experiencing the death of a child in Pakistan, a society in which marriage among close relatives is common. Analysis of data from the 1991 Pakistan Demographic and Health Survey reveals that first cousin marriages increase a couple's risk of enduring the death of one or more of their children. These couples are 1.18 times as likely to have a child die by its fifth birthday than couples not related by blood net of other factors associated with child mortality. Elimination of first cousin marriages would contribute to a modest decrease in the proportion of Pakistani families suffering the death of a child.