The grandson is oblivious to the situation?

If I had concerns I about the client's welfare I would talk to the grandson if you don't know any of the other family members.  I had a client that I had concerns about a few years ago.  The financial planner that the client dealt with also had concerns about her.  He talked to the client's kids who lived out of town and they were convinced she was just fine.  Finally a sister stepped in and helped out with the situation.

As a side note, it gets tough when clients head down that road.  I've been fortunate that when I did hit situations like that there was always a family member that stepped in to help the client out.

You have met this grandson, so that's a good place to broach the topic. If there is no one you are aware of, I would contact the county Aging Council. My understanding is that every county in the US has one, and they are Federally funded. I have had so much contact and support from more than one, and every time it's been amazing.

One way to open that discussion is "Let's make sure you have the specific team and support for your needs, as we discuss this complex topic with you. Who would I make sure is included?"

Even for hospice, I like to use a version of that phrase "special team" so they understand everyone is on their side and in it with them, not for them.

@dkh There's professional ethics - which might be violated if you talk to the grandson.

Then there's personal ethics that say-  I'm concerned about these people so I'm talking to the grandson.

I go with personal.

Come and get me ethics police.

I don't think the grandson is oblivious. I'm getting more of vibe that the client is a burden he's stuck dealing with.  I want to talk with someone that is going to give a hoot. 

This client is so kind.  Always calls me friend.  Sends me Christmas cards.  Yes, Ironman, it hurts to see the decline.

The ethical side of talking to family was a concern.   Thanks sjrcpa.     CGMC- right!

qbteachmt -  I like the "special team" idea.  We do have a COA in our county.

Thanks everyone.  

I'm experiencing this issue as well.   I've been considering adding something to the organizer about whether the client would like me to have the contact information of a trusted relative or friend in the event that they are having difficulties organizing their tax information, and then include an authorization form for them to complete and submit for us to keep on file.  Is anyone else doing this already? 

There oughtta be a law. Well, in Arizona there is. Arizona Revised Statutes Section 46-454.

“C. An attorney, accountant, trustee, guardian, conservator or other person who has responsibility for preparing the tax records of a vulnerable adult or a person who has responsibility for any other action concerning the use or preservation of the vulnerable adult's property and who, in the course of fulfilling that responsibility, discovers a reasonable basis to believe that abuse, neglect or exploitation of the adult has occurred shall immediately report or cause reports to be made of such reasonable basis to a peace officer or to the adult protective services central intake unit. All of the above reports shall be made immediately by telephone or online.”

“M. A person who violates this section is guilty of a class 1 misdemeanor, except if the failure to report involves an offense listed in title 13, chapter 14, the person is guilty of a class 6 felony.”

https://www.azleg.gov/ars/46/00454.htm 

@pamdory " Is anyone else doing this already? "

No, but I probably should be.  The problem is that in most cases we already have lines of communication set up, and in a few the client has no one who cares.  

There are a lot of Eleanor Rigby's in the world.

All the lonely people
Where do they all come from?
All the lonely people
Where do they all belong?

@BobKamman In the  case of suspected abuse or neglect, I don't consider contacting authorities an ethics violation-real or potential.

I think OP was thinking these people need assistance; as opposed to they were being abused.

It's easier to spot abuse than to recognize neglect.  In both cases, it's difficult to determine when a line has been crossed and either family or the law should be called.  

True.

"It's easier to spot abuse than to recognize neglect."

And then there is apathy. You cannot claim dementia when the person seems of sound mind, and just has an attitude. Sure, they're not considering the consequences (especially that others will have to deal with the ramifications), but that isn't actionable from a legal perspective. I've run into this a number of times.