Hello Mira:
I used the 7th house to represent your grandfather. I suppose the 7th could be the father of the father, but if it is the father of the mother, the 7th could represent him anyway to avoid confusion with the ASC.
He is ruled by Venus which is in his 12th house of confinement. It is dignified by being in its own sign, so I'd say he feels ok about his passing (could mean he is strong, but I don't think in this case it applies). His 8th house of death is ruled by Jupiter. Venus makes an applying sextile to Jupiter (he meets his death), according to the ephemeris, in 9 units of time. Since Venus is in a slow fixed sign but in a cadent quick house, we should assign the time as between fast and slow - 9 weeks (not 9 days).
You don't say why it is important to know if he will live, but with families that are waiting and being responsible, these things are pertinent. Horary is not always right, especially if there is a mistake in the reading, so get more people to decipher your answer, please.
-Barbara