The Follow Through Part of the Brain

So why is it sometimes the "follow through" portion of the brain doesn't seem to connect with anything else?

I was looking all through my parents house for some mail that an insurance company said that they'd sent (and I had no reason to doubt them) I had gone through all the stacked up mail on the living room, the dining room, beside the computer and all its stacks of printed email (there's an age distinction right there - I only print things if I need to take them with me or write on them.) No sign. I addressed the issue with the vendor as best I could anyway, but having mail disappear when i just went through piles and piles of it really seemed strange.

My sister gave me a clue. She thought she saw mom stash mail into the ginormous pile of coupons that Mom likes to go through. (She doesn't actually do anything with the coupons. I've just decided it's her way of shopping.) She couldn't have put mail in there. Right? Could she have? I finally asked. Mom is there any chance that there is mail in your coupon stack? "Oh yes. It looked important so I put it here."(Allegedly to give it to my brother but that never happened). In that stack, were over due notices, a cancellation letter, and a letter that I'd asked to be sent a year ago. "Mom these are really important pieces of mail." Talking to a wall. My dog listens to me better. This is someone who does not have dementia at all, just doesn't get it sometimes.

I grabbed their phone and quietly left the house and proceeded to rant about it to my sister, while I was standing on their driveway. My sister was sympathetic but amused. Mom had put it aside so that my father wouldn't bury it on the kitchen table, and that my brother should see it, but that part (the follow though) didn't happen. Never mind I can find things on the kitchen table. Never mind that burying something in a different pile usually doesn't help, and offers no protection.

Is this our fate? Do parts of our brain stop talking to each other?

I've set up a box titled "Mail" where my mom should put important looking mail into. I explained the idea a few times. I know it's not going to work, but I have to try.