First: I've been seeing a grey squirrel in the yard of the house on our left (facing the house.) Just me. No one else. I even saw it on our front porch, but it turned and ran even before I could call anyone.
So I'm nuts, obviously.
Until, one day, this high piercing cry, repeated like a car alarm and coming from the back yard. We all piled outside onto the porch, and I spotted this on the fence across the next door neighbor's yard:
The silly squirrel was giving an alarm at the top of his voice that went on for almost 20 minutes.