You might check your county social services department to see if there is some type of family mediation service available. If not try a church or social worker/therapist office.
If you don't have a "family sage," see if your county has a family mediation service. Some do. If not, does the biggest troublemaker go to church? Invite her pastor to mediate for your family.
JAMS is a well known agency that does mediation. You might want to see what they offer. I have a friend who works for their NY office. Not an endorsement, just a place to start.
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