Adult step-children and estate

Louisiana

My stepfather died in 2006 and my mother died in 2007. My stepfather has 2 adult living children and one deceased adult son. My mother has 3 living adult children and two deceased adult son and daughter. My mother had a 401K and investment money in her estate in her name only and has financially supported my stepfather for the last decade. Do my stepfather's adult children have a legal right to the money?What is the name of your state?

Did she leave a will and are these items mentioned in the will? If so, then the designations in the will CAN NOT not apply IF she also signed a beneficiary designation form and submitted them to the companies holding each account. Has anyone checked with the companies holding each account to see if she named designated beneficiaries outside of the will?

Wasn't stepdad's estate probated? His kids would be entitled to their intestate share of their dad's estate, if no will, or whatever the will share would have been of their dad's estate.

What did mom do with Stepdad's will?

What SHOULD have happened is that stepdad's estate be probated after his death, then mom's estate after her death, including whatever she was entitled to from hubby's estate, plus her individual assets, and whatever she then owned via jt ownership.