This section addresses the concerns and questions that people and their families often face when they have been repatriated or are in the process. Identify your case and know the options you have to solve it.
If you have Mexican nationality and your child was born abroad, you can register him/her at the Consular Office of Mexico abroad in order to obtain Mexican nationality.
Requirements:
1.Certified copy of the foreign birth certificate of the minor to be registered
2. Current official identification with photograph of the minor to be registered
3. Certified copy of the birth certificate issued by the office of the Mexican Civil Registry or Mexican Consular Office of the father, mother or both
4. Official identification with current photograph of both parents. Both parents must present themselves with the registered or designated person with power of attorney issued by Mexican authorities (Mexican Consulate) at the Consular Office.
For more information consult here