Mighty Girl Effect

The mighty girl effect, also called the eldest daughter effect, is the documented pattern by which fathers whose firstborn child is a daughter tend to hold less sexist attitudes and recognize gender inequality more readily than fathers whose firstborn child is a son. Researchers in the United States and United Kingdom began examining the pattern in the late 1970s, with a substantial body of published findings following from 2011 onward, and studies have tied it to measurable shifts in fathers' voting behavior and their support for gender-equity policy. The effect is specific to a firstborn daughter, whether biological, adopted or a stepdaughter, rather than to daughters born later in a family, and the shift in attitude has been shown to grow stronger as that daughter moves through childhood into her teenage years; researchers note the underlying mechanism driving the change is still being investigated.