Washington Revised Code Title 48. Insurance § 48.46.320. Dependent children, termination of coverage, conditions

Any health maintenance agreement which provides that coverage of a dependent child shall terminate upon attainment of the limiting age for dependent children specified in the agreement shall also provide in substance that attainment of such limiting age shall not operate to terminate the coverage of such child while the child is and continues to be both: (1) Incapable of self-sustaining employment by reason of developmental or physical disability; and (2) chiefly dependent upon the subscriber for support and maintenance, if proof of such incapacity and dependency is furnished to the health maintenance organization by the enrolled participant within thirty-one days of the child's attainment of the limiting age and subsequently as required by the health maintenance organization but not more frequently than annually after the two-year period following the child's attainment of the limiting age.