if she was Disabled on SSI before 22 wont be a application, if she was Disabled before 22, they probably will start it automatically as soon as they see you put in for your retirement, if they dont call them, will have to answer a few questions but will not need to apply again or anything, its actualy a Federal law Disabled before 22 when Parents are Retired or Deceased they automaticly switch over if you have enough credits for it She will get 50% of whichever parents amount will be higher