It’s weird. My sister is as conservative as me. But her daughter (my niece) lives in Southern CA and is JUST LIKE your parents. It’s the reverse situation. My sister can calmly discuss the facts with her until the cows come home, but all my niece can say is “Where did you hear that? Fox News??” is a most snide manner.
The answer to that “where did you hear that, Fox News?” is
“No, not at all ... I got it at the same place you got your information.”