Not just anyone might challenge the validity of a Will. Though state laws differ a little, all require that you be connected to the Will in some way. Usually, you should be able to show that you would have received more from the decedent, if he or she had died without a Will; or if she or he composed an earlier Will that left you more than the present Will.
Concern 2: When can I challenge the Will?
Question 3: How can I reverse a Will?