Over the years, my parents and other relatives have told me things about my family that they were eyewitnesses to or involved in. I know typically, you'd cite another person's knowledge as an interview, but these conversations were informal and no notes were ever taken. I just "know" the information because I've heard the stories several times.
Obviously, I know it would be best to get this information recorded through a formal interview so that future generations can have access to it. But if it's not possible to do this, would you still cite it as an interview? Or would it just be tradition?