How do i change a wrong last name registered in a birth certificate?

My son was born in Mexico, His father and me registered him with his last name, when i came to USA i found out his father has a different name,how do i changed the name given in the birth certificate?This is huge mess i know! but still i must do something for my son! I have a DNA test, a court order from the judge granting the change of name, but my son was born in Mexico, so, neither vital statistics can change his last name.

Does that mean only in Mexico somebody can fix this mess?

Does this matter need a lawyer?How do i change a wrong last name registered in a birth certificate?
You will probably have to get an attorney and go to court. That is the only way I know to have a name changed legally. Call the County Bar Association in your area and explain the situation, they will refer you to an attorney that does that area of law.How do i change a wrong last name registered in a birth certificate?
I am a wee bit confused. Do you mean that the man whose name you put on the certificate is not the father? Or do you mean that the name is spelled wrong or something? I would contact immigration and see if they can tell you a bit more about what needs to be done in this case.

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