After Dad died 8 years ago, Mom sold the house and used the money to build an in-law apartment off the back of my sister's house. She's been there ever since and is now 86 y.o. I live close by, and until recently my primary role had been in taking Mom out, to get her hair done, shop, go to doctor appointments, etc. My goal was to get her out - good for her mind and her body, and also to give my sister and her family a bit of respite. Recently, though, Mom's mobility issues, combined with her fear of Covid, have greatly changed her willingness leave the house. She's only gone out a handful of times in the past year, despite my repeated attempts to just take her for a drive, etc.
My sister is overwhelmed with work/Mom/Covid and every time I see her there seems to be a simmering rage just below the surface. I went to see Mom yesterday and Sis was barely civil to me. I want to help but don't know how. I've brought them meals ("My husband won't eat that") offered to stay with Mom so they can go away ("We don't have the money to go away - you should know that"), offered to run errands, anything I could think of. I've straight up asked what I can do to help and she just responds "There's nothing you can do."
I work full time and have an Autistic child so I can certainly relate to how hard it is to provide care for someone 24/7. I really want to contribute - I call Mom every day and bring her anything she needs but it isn't enough. We also have 2 brothers - one of whom lives on the opposite coast and contributes nothing. The other is close by but lives from one self-made financial crisis to the next and had soaked Mom for money so many times that it's safest to keep him at arm's length.
I've started to dread going over there as my sister's anger towards me is so hard to take. What can I do?