The OP didn't make that "quite clear" at all. Although it may be the truth we won't know until she comes back and tells us.
I read it as if he would prefer to let other family members have the money, as all his own money is going on care.
My own grandmother is in a similar situation (without the inheritance). She has to pay for her own care as she is not eligible for state care. She has enough money to cover her (probably) for the rest of her life as she is in her late 90s. This is perfectly fine, and none of the rest of the family begrudge it at all - every penny should be used to give her the best quality of life possible and there are no expectations that she will ever get any state care.
However, if she were to come into a large sum of money, she wouldn't want it - she is lucky enough to be "comfortable" and doesn't need any more money. I know for a fact she would prefer to see it given away to other family members, rather than have it included in her estate, spent on care, or inheritance tax in due course. The reason I know this is that she does the lottery every week - not so she can be a millionaire, but so that if she won, she would give the ticket to her grandchildren to claim our fortune! 
She, as could well be the case with the OP's grandfather, would do a deed of family variation so that the money could be better enjoyed elsewhere, rather than sitting in a pot until after she dies.