Is my mom getting the short stick?

So it's OK for him to be sole beneficiary (which is normal when married) but not her, if he dies first?? What has your relationship been with your stepdad and your stepsister like? In some states, I think, that no matter what, all possessions pass to spouse by law. The problem though is if she has Alzheimers, legally I'm not sure if she can sign off on something, so he's taking it upon himself to change things around now, while he's still kicking (for lack of a better term). He has POA on her I'm assuming, but there are ethical considerations here. My question is, why are they "re-writing" it to begin with? She's his wife...all assets including money should go to and through "her" (estate) if he dies first. I agree with you; all the money should go for her long term care. Then if anything is left over and beneficiaries are designated, a person in the family is usually assigned through the language of the will to make sure proper disbursements take place. I'm thinking they are setting up some kind of trust which in some cases can make things harder. AS her daughter, I would definitely get involved as well as ask if you can be added as co-representative on that trust or will. I also think ASAP you should consult an elder care attorney or someone in estate law.

There isn't really any way to force your stepdad to write his will to your liking.

What he inherits is his to dispense as he chooses.

However, in some states there is a legal way to fight the will if the spouse does not get a fair division of the martial assets. This may be the path you will take when the will is in probate. (Meaning after he dies). If your Mom is in a nursing home at that point...you can be sure the NH and/or Medicaid will be filing to challenge the probate of that will.

Is the plan for your mother with Alzheimer's to sign this will? Can you get letters from her doctors stating that she isn't competent? With those letters I would think you could challenge any will she signed going forward. Stepfather can leave his estate as he sees fit. Since you mentioned that this would be a rewrite, does your mother currently have a will? A consult with a lawyer might be your best move to see what your moms rights are in the state she lives in.