I'm creating a story with a custom vampire spellcaster (MM 297), and I want her to use the gentle repose spell on her victims, to prevent them raising as vampire spawns because she buries them in her family crypt as trophies.
You touch a corpse or other remains. For the duration, the target is protected from decay and can't become undead.
The spell also effectively extends the time limit on raising the target from the dead, since days spent under the influence of this spell don't count against the time limit of spells such as raise dead.
Of course, the objective for the PC's is to find and kill her, and they will also discover all the corpses she hid in the crypt.
Can the PC's resurrect the victims with the resurrection spell? What happens to the bite effect that raises vampire spawns from a dead person, if that person is no longer dead?
[...] A humanoid slain in this way and then buried in the ground rises the following night as a vampire spawn under the vampire's control.
[...] This spell neutralizes any poisons and cures normal diseases afflicting the creature when it died. It doesn't, however, remove magical diseases, curses, and the like; if such effects aren't removed prior to casting the spell, they afflict the target on its return to life. [...]
(Please note that I specified the resurrection spell, and not the true resurrection one, because the true one removes any kind of disease or effect anyway)