Vashti is a fun-loving child. She likes to find the playful aspect in things. She sees her father's potions equipment largely as toys. She hasn't lost this view, despite--or perhaps even because of--lessons on potion making. She sees necromancy mainly as a way of making unusual toys and/or pets (she hasn't made up her mind on what the reanimated corpses count as). And because of her (limited) experience with necromancy, she isn't squicked by dead things. Sure, sometimes the stench or the maggots can be gross, but those can be dealt with; and then you have prime toy/pet-making material!