Can bedridden grandmother sign property transfer or relinquish rights remotely?

My father passed away 10 years back, he had a property in his name which was bought through his earnings. In the legal heir certificate 4 persons are mentioned as legal heirs me, my brother, my mother & my paternal grandmother. Now situation is my grandmother is bedridden and she cannot walk or travel much, we wanted to transfer the property name to me & my brother's name but due to some corrections in Revenue land records it is getting delayed. I have a few questions. My grandmother is willing to sign but she cannot travel to the Registrar's office, is there any other way to complete the transfer? In case of grandmother's demise before name transfer: do all her legal heirs also have to sign? (there are 4 male & 4 female children to my grandmother, & one male kin died 20 years ago they have 2 kins). Are there any other declarations that can be signed by her stating that she doesn't want any rights to the property? something like a Relinquishment Deed?