re: Questions on executing a will and/or estate distribution

If he was a TX resident, TX laws will apply to everything except land in LA. Thus, TX law will determine if his will is valid (seems doubtful) and TX intestacy rules will dictate who gets the property. If the chart linked by previous poster is correct, your aunt may inherit all of his property (if it is community). For LA property, aunt would get 1/2, son the other 1/2 subject to aunt's use for her lifetime or until remarriage.

Forced heir is generally not applicable in someone of that age. Also, it isn't really necessary since he inherits anyway if will is invalid.