All patients in the state hospitals for the mentally ill shall be regarded as standing on an equal footing. The patients, according to their different conditions of mind and body and their respective needs, shall be provided for and treated with equal care. If the relatives or immediate friends of any patient desire special care and pay the expenses thereof, such patient shall have special care and shall be provided with a special attendant as may be agreed upon with the chief executive officer. In such cases the charges for the special care and attendance shall be paid quarterly in advance.