Let’s assume you have a legally valid will but you’ve decided that it should be revised because of a change in your family’s circumstances. Perhaps all you want to do is add a newborn grandchild to the list of beneficiaries or remove your adult child’s spouse after a divorce. These are both common reasons to revise your will.

Resist the temptation to revise the will yourself. State laws control the validity of your will, and the laws in each state vary, so simply following an online template for revisions isn’t certain to suffice.

In addition, the amended will generally must be witnessed and notarized. A notary isn’t a replacement for an attorney who knows his or her way around applicable state laws. To ensure the validity of the will, rely on the appropriate professional.

Furthermore, in many states, a will that has provisions crossed out and changed in handwriting won’t stand up to legal scrutiny. The same is true for a will with a typed paragraph attached to the original. If someone is then “cut out” of the will or not added as promised, it could lead to challenges in court and possibly create discontent that causes a rift in the family.

Minor changes to a will can be made through a codicil or an addendum. However, it usually makes more sense to create a brand-new will, especially if changes are substantial or state law requires the same legal formalities for codicils and addendums as it does for a will.