(a) The words “child”, “children”, “issue”, “descendant”, “descendants”, “heir”, “heirs”, “unlawful heirs”, “grandchild” and “grandchildren”, when used in any will or trust instrument, shall, unless the document clearly indicates a contrary intention, include children born as a result of A.I.D.

(b) The provisions of this section shall apply to wills and trust instruments whether or not executed before, on or after October 1, 1975, unless the instrument indicates an intent to the contrary.