An internally displaced Afghan girl holds a child at a refugee camp in Kabul, Afghanistan May 31, 2016. (Photo by Mohammad Ismail/Reuters)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)

Members of a teenage girl gang convincing an unwilling recruit to join the gang, circa 1955. (Photo by Vecchio/Three Lions)

Jesinta Campbell arrives at “Bridesmaids” Celebrity Girls Night Out to celebrate the Australian premiere at Event Cinemas George Street on June 14, 2011 in Sydney, Australia. (Photo by Lisa Maree Williams)

In this Friday, January 24, 2014 photo, Afghan refugee girl, Robina Haseeb, 5, poses for a picture, while playing with other children in a slum on the outskirts of Islamabad, Pakistan. (Photo by Muhammed Muheisen/AP Photo)

A girl marches alongside Salvadoran soldiers during the parade commemorating Independence Day in San Salvador, El Salvador September 15, 2016. (Photo by Jose Cabezas/Reuters)

A girl carries a rifle as she attends a rally by followers of the Shi'ite Houthi movement commemorating the death of Imam Zaid bin Ali in Sanaa, Yemen October 26, 2016. (Photo by Khaled Abdullah/Reuters)

A girl dressed as the Virgin Mary poses for a photo during the Lantern Festival celebrating the eve of the nativity of the Virgin Mary in Ahuchapan, El Salvador September 7, 2016. (Photo by Jose Cabezas/Reuters)