If you are on good terms with the person who is attempting the parental alienation, and someone else on the other side has warned you that they are aware of this person's efforts (cuz i cant figure out what the situation is by your description), then i would warn the parental person that parental alienation is indeed something they could be punished for. The judges dont like it. Im not sure what kind of crime it is, or if in all states, but it is becoming an issue.