When my mom has noticed switches in the past, she got freaked out and asked if I had MPD and said I was scaring her -_-;; So, I've decided never to tell her and we've gotten a lot better at switching more discreetly around her (or just not at all). I have no idea why, but I get the feeling that my dad would be completely understanding, but I know he'd tell my mom so I can't tell him either.