A/N: originally written for humanveil on AO3 for an exchange in 2020, I forgot to post it here until now. If I'd written it now I might not have used the term "mortals" since while hard to kill the Addamses aren't entirely immortal...oh, well, not changing it now.
It was sometimes said by mortals that blood was thicker than water. When Morticia had first heard that, she hadn't thought much of it. It seemed like stating the obvious; not to mention that if it wasn't, it would pour out of people far too quickly, making a mess and giving you no time to savour it. And for some reason people tended to get upset when she pointed out that blood also tasted better. However, it was certainly true that the Addams family was bound together by blood. In a far more literal sense than most families, in fact.
It was blood magic that shielded the mansion, rituals performed over centuries keeping the surrounding wasteland beautifully desolate no matter the time of year, and preventing the mansion itself from falling apart even though it had been condemned five times. They used blood magic to summon spirits, to reanimate the dead, to curse their enemies. More than anything else, it was blood that made them family. Morticia opened a drawer, and paused for a moment as she looked at the array of knives there, before selecting one. She turned to Margaret. "It's time to truly become one of the family."