This is somewhere between a random thought and a "dead Barb" thought.
Going through the list of people who would be able to do a damn thing come her passing, the Weston relatives seem like the best bet. They're geographically close and, if not emotionally close, I assume they have enough propriety to not leave the body of next-of-kin at room temperature for an indefinite period.
But then the thought occurs: Every time Chris has sent out distress calls for relatives to come "help" care for Barb, he's never called on the Weston side. He's always called on Cole, David, and Carol, and the latter two aren't even her children. (Given they were independent adults when Bob remarried, they only technically qualify as stepchildren.) We know Chris knows a little about Barb's family turmoil, but I wonder what else had to be said to make him assume they're not an option, period, the end.
Or if anything had to be said. Cole, David, and Carol, for all intents and purposes, are abstractions, people Chris doesn't know, so they can just as easily fit the slot of caretaker as any other. Chris has, however, been to a few Weston gatherings, so, even if his ability to read the room is limited, there must've been something in the air to let him know that fealty is non-existent.