Section 16S. The secretary of health and human services shall coordinate the purchase of behavioral health services for children to promote economy and efficiency and improve service delivery, thereby integrating services provided by the executive office of health and human services into a comprehensive, community-based behavioral health delivery system. The secretary shall establish guidelines for the department of children and families, the department of youth services, the department of public health, the department of developmental services and the office of Medicaid for the delivery of behavioral health services to children, including children subject to proceedings under sections 39E to 39J, inclusive, of chapter 119, pursuant to which the commissioner of mental health shall be consulted in the design and implementation of the commonwealth's behavioral health services for children; and the secretary shall consult with the commissioner of early education and care and the commissioner of elementary and secondary education to establish similar guidelines for those respective departments.