Showing that a testator, or person writing a will, was suffering from “undue influence” from a person that benefited from their will is a common way to contest a will. The most stereotypical situation where this arises is when a dying person marries or makes a new friend very late in life. There are a number of factors that a court will look at in Texas to determine whether or not an individual was “unduly influenced”.
The mental state of the individual writing the will is a factor that will be considered. If a person is mentally or emotionally weak then there is a greater chance that the will might not be valid. Also, if the person that is accused of unduly influencing them had some sort of power over them then there is a good chance that a court might invalidate the will.
In cases of undue influence the court does not always throw out the will entirely. Sometimes a court will only eliminate a particular section or provision of the will. In this case, the court will then interpret the will without the suspect gifts or reform the will to what it would have been if the bequest that was a result of undue influence had never been made. Exactly what happens is very fact dependent and can become complicated very quickly.