All U.S. citizens are required to have a passport when traveling internationally, including children. You may obtain a passport at a post office, but be sure to check beforehand if the post office near you provides passport service. Make sure to bring your child's birth certificate as well as identification for the mother and father. Both parents must consent for the child to receive a passport and to travel.
If you and your child are not planning on traveling internationally, a copy of the birth certificate will work. This is especially helpful if you are traveling with children from different unions or if the mother kept her maiden name.
Immunization records are helpful when traveling abroad. It is especially useful if your child becomes ill and will require a physician.
If the child you're traveling with is not yours or if you're divorced, you will be required to show proof that you have permission to travel with the child.
