A person under the age of eighteen ... may be a member of a registered society unless provision to the contrary is made by the society’s registered rules and may, subject to those rules and to the provisions of this Act,
(a) enjoy all the rights of a member; and
(b) if between the ages of sixteen and eighteen, execute all instruments and give all receipts necessary to be executed or given under those rules,
but a person under the age of sixteen shall not be a member of the committee, trustee, manager or treasurer of the society.