Well, when my husband died, his family was around for about 2 1/2 weeks. . . . And that's only because we had some complications with the memorial service. After that, as far as I know, they all left me to deal with everything else alone and they all went back to their lives and picked up where they left off as if nothing happened. And they care way less for me than they did for him, so I don't really see much effect.
My husband's grandkids may get some money as any money left after my final expenses are all paid goes to them.
My sister-in-law will probably be upset, but she has a family of her own so she'll eventually get over it. I think they'll all get over it and, in the end, everyone will be better off. Particularly me because I'll finally be free of the prison that is my mind & body and back where I want to be which is next to my husband.