When a loved one passes away, people are sometimes unprepared for the contents of the will. In some cases, the will is dramatically different from what they were expecting. When that occurs, they might choose to challenge the will. This isn't something that is easy to do; however, it can be done if there is a situation that would invalidate the will.
If the person who was executing the will wasn't legally able to do so, the will might be contested. This would be the case if the person wasn't mentally capable to fully understand what the will would accomplish when he or she died.
If a person was tricked into signing a will or if he or she was forced into signing the will, it might be able to be invalidated. These points can be difficult to prove, but if they can be proven, they can be effective. This means that if the person was pressured into writing the will or if he or she signed the will under deceptive measures, the will wouldn't be a valid will.
When a person executes a will, it must be done so in accordance with state law. If any of the points, such as witnesses, weren't met when the will was executed, it can be ruled invalid.
Before challenging a will, you should understand the process. You should also know that the process will likely affect personal relationships. If you feel the need to challenge a will, you must first determine the grounds for contesting it and determine if you have the evidence necessary to get the will invalidated.
Source: AARP, "Where There's a Will ...," Nancy Mann Jackson, accessed May. 28, 2015