I had a high school buddy move to Mich. just after graduation. We fell out of touch for about 25yrs until I got his phone number from his brother who I ran into a few years ago. When I called him on the phone he had a real Midwestern accent. He said no one ever told him that,probably because he sounds like everyone around him lol. My DW had a friend who moved here from Kentucky in early 90s when we met her she did not really have a southern accent. She moved back to Kentucky about 10 years ago and a month or so ago I talked to her on the phone. Holy moly her accent is back lol, I barely recognized her voice.