Agreement signed at Global Equality Caucus meeting in Argentina
Officials from across region attended launch in Mexico City
Funcionarios de la región asistieron el lanzamiento en México
Measure also defines family as a man and woman with children
Aldo Dávila a vocal critic of country's government
Ryan Fecteau and Aldo Dávila praised for leadership
Aldo Dávila a vocal critic of country's president, corruption
Vice president spoke with country's president on Monday
Bodyguard shot one of the assailants who approached vehicle