I want to send my deaf, mentally challenged and now blind sister activities she could enjoy and take part in. Advice?

Don't feel guilty for something you have no responsibility for! And your love is not failure. You just need information. And THIS is my area of expertise! Years of working with children with sensory needs.

The sensory abilities of touch, taste and smell are her link to her environment, will stimulate her brain, and will reinforce her experiences that she still remembers.
Touch includes textures, temperatures, vibration.
Since she probably doesn't get outside often, think of natural items for touch: box of rocks and leaves and shells, sand/rice in a soft bag, spray bottle, hand-held fan she can turn on and off by herself, a light box they should use with her daily for Vitamin D, and offer her cold packs and heating pad (lock the button with superglue to NOT go to Hot).
There are lots of sensory fidgets available, squishy balls, nubbly balls, that sort of thing.
And vibrating objects are very nice: massagers and stuffed vibrating toys and pillows (I'll provide a link to a wonderful on-line catalog). Also, those "feely" toddler books, and activity mats and boxes for infants. Stretchy fabric and exercise bands she can pull (resistance is a kind of sensory input to the muscles and joints). Those baby pop-beads, and plastic links she can work herself (push is also good resisitance). You can make fabric texture boards wtih stiff cardboard and pieces of corderoy, velvet, satin, bubble wrap, sandpaper, anything really! And be sure the carers take off her shoes and socks and try textures on her feet! If they can put on lotion, that is nice, too.

Dolls with lovely hair and faces to touch, and highly textured clothes that she can dress the baby herself. Nicely shaped toy animals she can recognize like dogs and horses. Small figurines to hold, can be comforting.

You can make a smelling activity: small containers (old pill bottles work) with cotton balls soaked in natural oils and food-grade flavorings. Punch holes in the lids. Put them in a box that seals up. She should be able to open it. Go for strong scents that might call up emotions and memories: Peppermint, Rose, Cinnamon, Pine. You can use teabags, and fagrances for candles are found in craft shops. Just be sure to refresh the scents occassionally.
And of course taste. Eating and drinking sometimes requires supervision if she has any danger of choking.
I would also ask if she can sit in a rocking chair or glider chair every day, with a way for her to move the chair herself. If she is sitting all the time, her brain also needs and enjoys motion.

I hope this feels doable to you. And that her group home staff are able to help her get stimulation and actively partipate in her preferred activities!

Besides the fine suggestions for tactile delights and other pleasant pastimes, I’d like to provide a generous hug to you for you efforts, but please be aware that as a very significantly limited adult, it is likely that she does not regard herself as “terribly sad”.

Her life now is predictable for what it is. I doubt that she expects or misses anything, because she’s all but never known anything else.

I wonder if she might enjoy a gentle chair massage, if she could be seated in a comfortable massage chair, or if not, perhaps massage of her hand and arms and legs and feet. This might be good for her circulation as well.

Perhaps she might enjoy “manicures” with fragrant hand creams or perhaps “samplers” of healthy flavors that she likes.

If you are feeling “deep guilt and failure” because you are unable to take on an almost impossible task, please realize that as caregivers, we are forced to confront the often heartbreaking task of doing pleasant things for Loved Ones who can benefit only slightly or perhaps none at all from what we do.

It would be “failure” if we stopped trying. No failure for you, but the frustration and sweetness of a kind and loving sister. So please consider yourself hugged.

Thanks for jumping in so quickly with your suggestions! I’m going to try out the fidget blanket and look for scented play dough and floam.
I’m so pleased to have come across this site! I will be sharing it with many of my friends and family.

A fidget blanket may be something she would enjoy:

https://www.amazon.com/Healthy-Seniors-Blanket-Suffering-Dementia/dp/B097HGXRWC/ref=sr_1_5?crid=25OQYGV8JU8VZ&keywords=fidget+blanket+for+adults&qid=1644449881&sprefix=fidget+bl%2Caps%2C147&sr=8-5

While advertised for 'seniors with dementia', an activity blanket such as the one linked above isn't just for seniors with dementia but also good for autistic children and all sorts of adults with disabilities. Look on Amazon for other 'fidget blankets' if you think your sister may enjoy something like that.

Best of luck.

Have you ever consulted with the Braille Institute? They might have suggestions. They work with all kinds of blind and blind/deaf clients.

How about a baby doll? I got one for my mother with Alzheimer's. It's so soft and comforting that everyone wants to hold it. I even find the nursing home aides holding it and rubbing it's back like a real baby. Ashton-Drake has these theraputic dolls. She may also like a stuffed kitty or dog.

How about topographical maps or sensation books that have various tactile pages. As I recall there used to be some good ones for young children that had pages with things to button and unbutton, hook and unhook, soft, smooth…things like that. They were used to teach children about words and how to do things but it doesn’t matter what they are supposed to be for as long as she gets her own pleasure out of doing whatever it is. Another thought I have is an essential oil bracelet or necklace and trying various scents that might please her, as long as she isn’t prone to putting things in her mouth or swallowing things she would be able to use the scent whenever she wanted this way but I would start gradually, maybe one drop to try and then work up or even dilute with a carrier oil first and one drop of that. I believe there are practice instruments like drums that have earphone capability so everyone around her doesn’t have to listen but she could create and feel the vibration/music. I don’t know enough about them to point you in the rite direction but it might be worth checking out.

Please get over the guilt, you certainly aren’t abandoning her or not doing much for her, you are here and I’m sure elsewhere, looking for ideas and you obviously care about her very much. I’m sure you visit as well, she isn’t alone and sometimes there is only so much we can do. So many with her challenges are truly left to exist and forgotten about more than your sister obviously is, once they are in a safe place with others caring for them. She is one of the lucky ones, she has you.

Good luck, I have no doubt you will find the perfect thing!

Have you ever heard of "Joy for All - Companion Pet Cat?" It's a battery operated, life-like stuffed kitty. Also "Perfect Petzzz." Looks like it could be a great idea.

You said she has a little bit of communication using small sentences so I think that is something to explore further.

Would she enjoy the interaction with other humans who can teach her braille and/or sign language? Whether she actually learns either skill doesn't matter, it's about the stimulation

Can you take her somewhere for a couple hours maybe 1-2 times a month like out to breakfast or lunch? The zoo? A park? The beach? The mall to walk around & smell and feel different things?

She may not be able to see or hear but she can smell, taste & feel. She'll know the sun, the rain, the wind, the smell of the ocean, fresh cut grass, the vibration of a train, the feeling of sand, a sea shell, an animal's fur, holding someone else's hand, a ride on a merry-go-round, a pumpkin patch, a drive in the car, etc.

Visiting her every time in that setting is almost inhumane & she has to live there!! Maybe taking her out for a couple hours & doing something you both enjoy would make you & her feel better. Your soul will NEVER regret what you did for her.💛

I would look for scratch and sniff books and sensory books. Plush sensory educational animals that have buttons, zippers and velcro. Maybe a box filled with things of different textures. 

Is she able to go outside at her group home? It would be nice for her to feel the sun and smell the flowers.