How to get passports for 14 & 16 year old American Citizens taken to Mexico as children without passports?

Question: I am living in the United States but took my sons to Mexico when they were 3 and 5 years old. We registered them in Mexico as dual citizens

Source: http://www.us-passport-service-guide.com/how-to-get-passports-for-14-16-year-old-american-citizens-taken-to-mexico-as-children-without-passports.html

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