A recent Huffington Post article titled "What Happens When You Disinherit Someone From Your Will" recommends that you do everything possible to document the reasons behind disinheritance, if that is part of your estate plan. Should there be a specific event resulting in disinheritance, it should be identified. If this change of heart was not in a prior version of the will, then the drafting attorney should seek and document the testator's explanation for why the disinheritance was not in an earlier version of the estate plan.
As you can imagine, this is not just a quick phone call with your estate planning attorney. No, you really need to sit down with your attorney and make sure it is done correctly to avoid issues after you pass on.
The original article cautions that a will represents the last words of a person and is a lasting record of their intention to favor certain individuals over others. From an emotional standpoint, this can be critical. Intentional or not, the disinheritance of a child is like saying that he or she is loved less than the others who are still getting something in the will.
The article admits that there's no foolproof way to disinherit beneficiaries. When an individual decides to disinherit his or her survivors, there are commonly consequences. Sometimes a disinheritance—even when it shows the testator's true feelings—may not be worth the trouble of its emotional and financial impact.
Reference: Huffington Post (April 9, 2014) "What Happens When You Disinherit Someone From Your Will"