Authorizing the district court upon request of the grandparent or great grandparent of an unmarried minor child to grant visitation rights on behalf of the child and the grandparent or great grandparent; providing for the filing of a motion or petition for visitation rights by grandparents or great grandparents; providing for mediation; repealing certain requirements for court determination of the best interests of the child and of no interference with the parent child relationship(mk)