I’ve been combing the archives and have collected a bunch of information together about how to get my application together. I’ve read that I need notarized copies of my mother and father’s Taiwan passport as well as a copy of their marriage license. My father passed away a few years ago. Does anybody know if I still need to notarize his passport and still need the marriage license? Or can I just apply under my mother?
Yes, you still need their marriage certificate if they were married, and your father’s death certificate, iiuc.
You could confirm with TECO in your area or the headquarter of NIA at Taipei. You could send an email though it may take about a month or more to get a reply. Or you could just prepare those documents in case you need them.