We study family income inequality in Mexico from 1988 to 2010, when among married couples, the share of income contributed by females grew from 13 to 23 percent. However, the correlation of married males' to married females' earnings has been fairly stable at 0.28, one of the highest correlations recorded across countries. We follow Cancian and Reed's (1999) methodology in order to determine whether married females' income equalizes total family income distribution. We investigate several counterfactuals and conclude that increased female employment has contributed to a decline in family income inequality through higher married females' labor participation in poor families.