In the case presented, a recovering alcoholic father, Bob, has sole custody of his two young sons, Aaron and Robbie, ages 4 and 2, after their mother repeatedly physically abused them in various ways. The mother currently has no contact with the children. Bob has a new wife named Betty who left her previous married due to abuse by her alcoholic husband. Betty is now pregnant, but has growing concerns about Aaron and Robbie's violent tendencies toward other children that involve choking and slapping, and fears that these violent behaviors might be directed toward the new baby. Both Bob and Betty are fearful and frustrated with the two boys, and react using roughness, only adding to Aaron and Robbie's aggressiveness. How would experiential family therapy be used to strengthen the family?

What role would the therapist play?