My cats are really good at staring at the walls and meowing when I'm watching a scary movie. I think they live to freak me out! I had one that would attack the wall when I watched scary movies, but not when I watched other movies. What do they know that I don't?
When our GS got old and deaf, she would run to the door and bark when my husband laughed. She though his laugh sounded like someone knocking on the door. One of my older son's first sentences was "ush olly ush". We didn't know what it meant until we were out for a walk and some dogs barked at us, and he said it. We realized that it was "Hush, Molly, Hush".