One potential concern you might have while creating or amending your estate plan is whether somebody might challenge your will after you are gone. Nobody wants a messy probate fight for their family, but at the same time, the terms of your estate plan should be what you want them to be. They should not be dictated by distant relatives or anybody who feels entitled to a large share of your estate.
It may come as a relief to learn that the list of people who can challenge a will is fairly narrow. Only "interested persons" can potentially file a challenge during the probate stage. "Interested persons" includes people with a property right or claim against the estate, such as children, spouses, heirs and creditors. At least you know that the entire planet cannot get involved.
Also, in order to challenge a will, a person must have "standing" under the law to do so. Generally, this means the person is named on the face of the will, for example as a beneficiary, or would inherit something -- or lose an inheritance -- if the will were found invalid. A beneficiary does not have to be related to the deceased to have standing, or even be a person. Charitable organizations can have standing, for example.
"Heir" means something different than beneficiary. An heir is a relative who would inherit from the estate if the deceased is found to have died without a valid will. Heirs can challenge a will if they believe they were wrongfully omitted or shortchanged by the terms of the will.
For testators hoping to avoid all of this, one way to deter challenges is to include a "no contest" clause in the will. This clause essentially tells beneficiaries to "take it or leave it." If a beneficiary challenges in order to get a bigger share of the estate, he or she could be disinherited entirely.
For more on this and other strategies, consult with your estate planning attorney.