der_kluge
Adventurer
I'm not sure how far you wish to go with that storyline, but it instantly have me some thoughts.
Doing whatever it takes to get his house in order... Sounds like he needs a business partner or investor. You know, someone who for a small favour could help out with some trade deals. Keep hold of this package until a certain person comes looking for it, no questions asked. Maybe house some guests, that sort of thing.
Oh, you need more time? Well, this amulet/ritual/brand will provide you with all the time you want/turn you into a minor kind of lich/infuse you with some level of immorality. There's just one catch...
There is a rent to pay for this new life. A rent paid in souls.
Basically, the reason for becoming undead sounds like a perfect reason for a devil to offer a pact. A minor kind of lichdom could work, but if you have trouble finding a suitable kind of undead there may be other ways for a devil to help out.
Hmm, that's an interesting take on it. That gives the paladin son a chance to actually redeem him, not just kill him and bury him. I'll have to think about that some more.
It's all the more interesting when you consider I'm planning on having the PC compete in a joust against his own brother - a brother who might also be receiving some unnatural gifts.