What recourse does a parent and grandparents have against a soon-to-be ex-spouse who deliberately and viciously seeks to use tactics to alienate a child (daughter) from the father and grandparents? Child is eight years old and highly intelligent enough to report tactics to father and grandparents.

Report it to the judge. As that a guardian ad liteum (GAL) be appointed to present the child's interests and have the GAL interview the child.