By contrast with findings from the United States, Andrew Leigh finds no evidence that the gender of the first child has a significant impact on the decision to marry or divorce in Australia. However, among two-child families, parents with two children of the same sex are 1.7 percentage points less likely to be married than parents with a boy and a girl. Surveys of parental attitudes suggest that this effect is more likely to be driven by fathers than by mothers. This finding is not consistent with theories of preference for sons over daughters, differential costs, role models or complementary costs, but is consistent with a theory of parity preference.