My stepfather died on 02/11/2001 and left his 50% of community property in a Residuary Trust which contained stocks to be used for the benefit of my mother. According to his will, when my mother died the remaining stocks were to be equally divided to 3 beneficiaries. My mother died on 06/01/2014. Which date would the 3 beneficiaries use to determine the value of the stocks for their stepped up basis? Would it be when my stepfather died on 02/11/2001 or when my mother died on 06/01/2014? I have received 2 different answers.