Include provisions for every possible asset in your will. If you omit anything, your disinherited heir can claim that you died partially intestate, or with an incomplete will, and can make a claim that the property omitted should pass according to your state’s laws of succession. If she is in line to receive a portion of your estate as an heir, she might then get a piece of anything you omitted even if it was your intention to leave her nothing.
State specifically that you are leaving nothing to the person you want to exclude. Don’t just omit mentioning them, warns the American Bar Association. If it is your intention to exclude your child and your state allows that, it may be best to leave them a token amount.
Add an “in terrorum,” or no-contest, clause indicating that if the person you excluded contests your will and loses that contest, then he receives nothing. This is usually only effective, however, if you are not excluding someone completely. It may be best to leave him just enough to make him think twice about risking its loss if he loses the contest.
Write a separate letter or statement giving your reasons for excluding the person you want to omit, and append it to your will. You can also back up your will with a videotape or digital recording explaining your reasons, but make sure you appear sharp and concise when you make it, and have witnesses present.
Safeguard against any claims that you are medically or mentally incompetent at the time you’re making your will by having a qualified professional present when you sign it, such as your doctor. You can also have your doctor make a notarized statement that you are competent, and attach that to your will.