I haven't lived with my mom for years but I still showed Amnesia's trailer to her when I visited her. She silently watched it and when it ended she casually stated that "You shouldn't play games like that. You'll see nightmares."
Tbh I haven't seen a single nightmare about Amnesia or Penumbras. There's been some grunts and brutes visiting in my dreams but they haven't been nightmares.