On one hand you might be doing them a favor by urging this couple to confront her declining health and consider an assisted living arrangement or possibly moving closer to a supporting family (maybe the kids?).

If you are aggressive or confrontational they will dig their heels in and make things as difficult as possible for you.  

Is it unethical or confrontational to not renew someone's lease if all of the occupants want to stay? 

I'm about to purchase several rental properties located 50 miles from where I live, and am confronted with the same challenge.

She tried confronting them, but had no success getting the items back.

I will start by confronting the tenant about having a guest for longer than 2 weeks, but I would love to get this done quicker than that.

I know other LLs that own the latter and they make lots of money but they have a super high tolerance for ******** and confrontation. 

My father has done realty on a more personal level where he as an individual confronts investors after setting terms on a house mortgage that the bank is willing to make a deal on.

Some people would just pay instead of having a confrontation so only act on what you are prepared to defend

Make sure any confrontations are where the cameras are setup.