In general, changes made to a Will must be affirmed as being made by the person who's Will is actually being changed.  You don't specify how you are changing it.  If you are doing it through a lawyer, then the lawyer will be able to ensure that the change is legally recognized.  If you are c hanging a Will that you have written yourself, assuming that your State recognizes the form of the Will you drafted, you must have changes notarized to ensure the legal integrity of the changed document.