Is it better to renew my 15 year old son's passport now or wait until he's 16?

My husband and I were married at the time we applied for my son's passport. Our family moved outside the U.S. My husband and I have separated but are

Source: http://www.us-passport-service-guide.com/is-it-better-to-renew-my-15-year-old-sons-passport-now-or-wait-until-hes-16.html

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