Tai Chi for the Immobile

I have been thinking of Tai Chi for the immobile. My grandma can't stand and has poor motor control over her limbs. I was wondering about exercises that are supposed to improve motor control and general fitness. Then these have to be modified to be done in a seated position. I'm told that the same rules apply for sitting as for standing: straight back, pelvis slightly rolled under and chin in (sraightening the neck).

Next is a set of 'stances' and movements that can help. I think I would start with some of the 8-pieces of silk brockade: pushing the sky, touching heaven and earth (although the arms of the chair might get in the way), shooting the golden eagle, cow turns to look at the moon, willow cools it's leaves and punching the wind. The other 2: White crane washes it's wings and shaking the tail feathers are not at all faesible. Perhaps placing the hands over the dan tien and breathing would replace shaking the tail feathers. I'll have a think about other Qi Gong that might work. I'll post again on this I think.

Before I go, I was thinking about her tilting chair. If the back doesn't fall forward too far then it might be possible to put some weight on her legs.

Of course all of this may be completely in vain, because 1, she's realatively likely to say, "I'll have none of this hippy rubbish", and 2, western medicine says that this is a neurological problem - part of the brain is dying so exercise shouldn't be able to help. We'll see..