My stepdad signed a "Waiver of Right's" to my Mom's estate. Does this invalidate any accounts where he is listed as the beneficiary? Does this invalidate NY state's spousal inheritance provisions (which I believe entitles the spouse to 1/3 of the estate)? He is also currently listed as her POA, should this be changed if he is waiving his rights? My Mother's health is rapidly declining, and I know her intentions were to ensure that what she had prior to this 4 year marriage went to her children.