My dad passed away in 1987 of lung cancer. It was right at the time when I was in college, and my brother was newly graduated from high school. My mom didn't know what to do. She didn't have anyone to take care of.
It took me a few years to recognize that she was pretty isolated. She didn't drive, ddn't work, didn't go to church too often.....After that, I tried to get her involved in any activity that I was involved in, so that she could feel like she was helping me, and so that she could get out of the house. One of the activities she did enjoy without me, though, was shopping. She especially enjoyed the dollar store. And this is where the hindsight kicks in.
Every time I would come to visit, she would have a "care package" for me. It would be several grocery bags of food that she had bought at the dollar store. A family of eight would have a tough time eating all of that, but when I gently tried to explain to her that I didn't eat that much, she got a hurt look in her eyes that just about killed me, so I continued getting the food for several years. I can see now that this may have been the beginnings of the Alzheimer's, but at the time I thought she was just wanting to feel needed.
Another thing I noticed, but didn't recognize, was that she had had a trainer come to her house a couple of years before, to train her dog in basic obedience. It was amazing how much that dog learned in just a couple of lessons! My mom learned how to do a hand signal to get her dog to sit and used the hand signal often, because it was so impressive to have the dog obey when she didn't even say a word. It was a couple of years after the training sessions, that my mom kind of "forgot" how the hand signal went. Instead of a definite signal with her hand, she would just fling her arm around and say "sit!" or she might say "go over there and sit down!" (and of course the dog didn't understand that.
And her cat. She would feed her cat five or six times a day. And then she would worry when the cat wouldn't eat (it was full).
If I had to put it into words, I would say at this time, she seemed to have less of an understanding of the relationship between what she wanted to accomplish and the right way to do things in order to accomplish her goal.
But of course, that's 20/20 hindsight. I didn't see any of that at the time. I just thought she was getting eccentric, probably from living alone for so long. My mom wasn't old, and Alzheimer's was something that happened to "old" people, so why would I even be concerned???