There is no set age above which a judge can take testimony, usually in chambers, from a child in a custody case. At younger ages, in Louisiana practice, the judge will usually only ask factual questions, not for an opinion from the child as to which parent the child would prefer to live with. As a child gets older, a judge is more likely to at least consider the child's stated desires, frequently around age 13 or 14 and older. The judge is not bound to follow the child's desires, however, as the best interest of the child is the controlling factor, and that may not be the same as the child's subjective desires.
The foregoing is intended as legal information concerning the question asked, but is not intended as legal advice upon which the requesting party may rely in guiding their actions. Rather, the requesting party should consult an attorney for a personal consultation and advice for a full consideration of their situation and rendition of legal advice. Additionally, by providing this general information I am not accepting any representation of the requesting party and I am specifically declining to form an attorney-client relationship with the requesting party unless agreed to later after further consultation and agreement.
Areas of practice listed are are areas of concentration in my practice. I am not board certified in any of the listed areas, and by listing them and describing my practice I am merely describing my experience and the nature of my practice.