for being a lousy father who purposely stunted his daughter Tabitha's magical development. Samantha then quickly married a second mortal whose name was Darrin so her daughter would not have to go without a father figure; and Samantha met him at the first Darrin's workplace, being too much of a busy homemaker to find a replacement elsewhere. Naturally, since she found another guy in such a short time that it was seamless, this guy was as big a jerk as the first guy, and also discouraged Tabitha from developing and using her witchly powers. Samantha keeps marrying jerks because she's a nitwit who drank martinis when Tabitha was still in Sam's womb. Good thing Tabitha has her good loving grandmother.
Samantha and Serena were switched at birth.Serena could totally be Endora's daughter. Aunt Clara is Samantha's real mother.
Samantha used her magic to change Darrin's appearance.Samantha has shown herself to be very protective of her husband, and may have changed the way he looks to prevent other witches who have antagonized him over the years from realizing who he was so they would leave him alone. Of course, her relatives would be none the wiser, but that was unavoidable.
Magic is symbolic of masturbation.Samantha vows to stop as symbolized by her marrying of an uptight non-magical man. The couple usually keep their daughter, Tabitha, from using magic. Nonetheless, Sam and Tabitha use magic at times when alone. Sometimes magic seems taboo. Aging sometimes alters magical ability and control.
Every case of The Other Darrin on this show was actually The Nth DoctorAunt Clara screwed up one of her spells and turned Dick York into Dick Sargent. She ended up doing the same thing to Louise Tate, Gladys Kravitz, and Darrin's dad, too. With some help from Endora, she altered everyone's memories as well as all pictures so that everyone (even Sam) thinks that's what they always looked like. Clara was going to undo all the damage later, but she accidentally turned herself into Esmerelda. This explains why Clara is neither seen nor mentioned in the later seasons.
Witches are normally polyamorousThe question of whether Endora and Maurice are, or ever were, formally married is never outright stated. They do not live together but are not explicitly divorced. In one episode, when under the effects of a love potion Endora nearly marries one of Darren's clients, without any mention being made of her needing to divorce Maurice first. The love potion in question was intended to make Samantha fall in love with her warlock ex-boyfriend and leave Darren. No mention is made of the ethical or moral ramifications of using magic to cause someone to commit adultery and breakup their current marriage. Meanwhile, most of the other witches and warlocks that appear on the show seem to be single, including all of Samantha's family.