Legal Question in Family Law in Louisiana

Her father would have to agree in order to change the birth certificate to show his name. You could do a simple name change that would accomplish that, but the birth certificate would only show the change of the last name. As long as you are not changing your name for some illegal purpose such as to falsely present yourself as someone you are not for gain, then it is not very difficult. I assume her father has some "custody" of the child, and if that is the case, then his permission may be necessary for even the hyphenated name.