When an adult family member sustains an injury in an auto accident, they have the right to make a claim or file a lawsuit on their own behalf. Even if you are the person’s parent, you have no authority to control their interests once they reach adulthood. When a person reaches age 18 or becomes an emancipated minor, Louisiana law presumes that they are competent. The presumption of competency only changes if the relative becomes disabled, is legally declared incompetent, or is incapable of making decisions about personal, financial, and other vital life issues.