My father sometimes doesn't use common sense, under the guise of doing whatever it is he wants to do, because he wants to do it. For instance, their dog has a knee injury and my father lets the dog go up and down stairs by herself, and he throws balls for her even though she skids on the hardwood floors to get them (exacerbating her injury). After dinner, he gives the dog their plates to lick, no matter what they've had, or even if the dog has had digestive issues that day. These are just examples. I don't know what to do with my dad when he's like this. What other signs of possible problems should I be on the lookout for?