This I believe comes down to the terms of the contract. If person X got your stuff upon your death, then being undead shouldn't affect it too much. There are ghost stories of people coming back from the dead, and then their spouse couldn't collect the death insurance. But again I think that would come down to the exact wording of the contract. Very many of these cases and no doubt they would push some new laws through congress on how to handle such things and death insurance and the case of undeath, resurrection, etc.
I think this would also be the case for undead spawn. Even if you got a judge to rule that undead spawn is the same as your child, unless you made an underage spawn, they would already be of legal age and you wouldn't need to take care of them. But this does seem a bit unfair to the newbies who need a head-up into undead society. So do you go by their age since birth, or age since death? Quite the legal headache, which is why we do these surveys from time to time.
