Haha, not when you have a four year old and two year old jabbering in the back seat.
True story. Happened a couple of weeks ago. My mother-in-law is a teacher at the christian school my 4 year old goes to preschool at. She picks him up on her way to school and (most of the time, at least) brings him home. A couple of weeks ago she was running late and forgot to get his backpack with his lunch on the way out the door. My four year old likes 'normalcy' and flipped out about not having his backpack upon arriving at school.
No biggie. Threw a coat on my 2 year old (still in jammies), put my keys in the front of the backpack and headed to town. A student met me in the parking lot, I handed off the backpack and took a quick spin around town before going home. All in all about 30 minutes from departure of backpack until pulling into our driveway. No fob the whole way home. Didn't get the 'need your key fob' message until I pulled into the driveway.
Thankfully Mrs. Squirrel leaves her fob here unless she plans on driving the Ex that day so I had hers for the return trip a few hours later. Still, never saw anything on the dash about missing the fob and didn't her any chimes, either. To say I got lucky that day is an understatement.