Doing Mom's will

What is the name of your state (only U.S. law)?Oklahoma

My parents were divorced in 1990, we thought. Now I am trying to get Mom's affairs in order and find out the divorce decree was never filed, so that means not divorced, correct? My dad re-married, twice, but Mom never did. What documents do I need to make sure there are no loopholes or problems when I go to file her will with the court?

Is Mom still alive? How are the assets titled? What assets are in play?

Well, this sounds like a legal nightmare. First of all...seeing as your father never LEGALLY divorced your mother...and has "re-married" twice..those marriages are not legal and he could be considered a bigamist.

You didn't specify whether your mom was still alive...so if she is, there are a lot of things to hammer out. The assets she is putting in the will may also belong to your father (depending on the marital law in your state)...so you need to inquire about that. They need to have a legalized divorce so as to avoid any more legal confusion.