The plugged casket radiates hate. Legally, your grandfather is alive inside it. Biologically, it's a brainless bag of engineered organs kept alive by obscenely expensive machinery set up with the specific purpose of depriving his descendants of their inheritance.
It drove your father to madness, something that would have pleased your grandfather. And it drove _you_ to the life extension biotechnology industry.
You've been fighting a trench war with your grandfather for decades now, and you're richer than he ever was, but you will never stop.
Hate, your grandfather taught you, is what keeps you alive.