- "I can heal the sick, an' even raise the dead--
And make you little girls talk outta your head!"-- Willie Dixon, "Seventh Son"
- Johnny Thunder, an early member of the Justice Society of America, got his powers from being the seventh son of a seventh son, born on the seventh hour of the seventh day of the seventh month of 1917.
- In The Seeker, a movie based on Susan Cooper's The Dark Is Rising series, Will is the seventh son of a seventh son, and destined to save the world from darkness.
- In Orson Scott Card's The Tales of Alvin Maker, Alvin is the seventh son of a seventh son, born with a caul, and is a powerful "maker"--a rare and powerful form of magic. The first novel in the series is even named Seventh Son.
- In the Discworld series, the magic number is eight, not seven, but the eighth son of an eighth son is a wizard.
- In Equal Rites, Eskarina is the eight daughter (eighth child, actually) of an eighth son, which isn't supposed to work, but somehow it does. Women are supposed to be witches, not wizards, but Eskarina is simply too wizardy.
- In Sourcery, we learn that the eighth son of an eighth son of an eighth son becomes a super-powerful "sourcerer", a being in touch with the source of magic, and almost too powerful for the world to bear. (This is one of the reasons wizards are discouraged from having sex.)
- In Septimus Heap, Septimus is a powerful wizard, and the seventh son of a seventh son.
- In The Forgotten Beasts of Eld, when Sybel is puzzled that Coren, an ordinary human, knows so much about the magical beasts under her care, he simply explains that he's the seventh son of a seventh son.
- In Dan Abnett's Gaunt's Ghosts novel The Guns of Tanith, Soric reveals that his great-grandmother was a witch, and that his father said it would come to him, as the seventh son of a seventh son. On the other hand, what it causes him doesn't seem very lucky at all...
- In Patricia C. Wrede's Thirteenth Child, Lan is the seventh son of a seventh son, and so a natural magician. Others point out to Eff that she's a seventh daughter, even if she is a thirteenth child.
- In The Last Apprentice, being the seventh son of a seventh son is literally a job requirement to be a spook.
- In Mercedes Lackey's Tales of the Five Hundred Kingdoms series, Sasha has some small magics, in part because he's a seventh son. Also, in One Good Knight, Gina mentions that three of her siblings have magical abilities.
"That kind of startled my parents, they had no idea that there was magic in their blood,but the sibs in question are the seventh born, the ninth born, and the thirteenth born, so that probably explains it."
- In The Secrets of the Immortal Nicholas Flamel, Perenelle Flamel is a female example. Being the seventh daughter of a seventh daughter allows one to speak to ghosts.
- In the Daughter of the Forest, the first book in the The Sevenwaters Trilogy, Sorcha is the seventh daughter of Lord Colum. Her six brothers are bound in a curse to be forever swans by her stepmother that only the seventh child can lift.
- The Doctor Who episode, "Terror of the Zygons" has a landlord who claims to have the power of second sight because he's the seventh son of a seventh son.
- In the Soap Opera Days of Our Lives, a shadowy crime lord called "The Phoenix" claims to be the seventh son of a seventh son and to have magical powers.
- In Charmed, a seventh son of a seventh son is revealed to be The Chosen One.
- In The Twilight Zone episode "Still Valley", a Confederate soldier met an old man who had magical powers because he was the seventh son of a seventh son. He also had a Deal with the Devil thing going on.
- Willie Dixon's classic and much covered blues song, "Seventh Son" claims various powers for the singer.
- Iron Maiden's album Seventh Son of a Seventh Son, and the title track, are all about this trope; the album was inspired by Orson Scott Card's novel, Seventh Son (see Literature).
- In the tabletop role-playing game Changeling: The Lost, being the seventh son of a seventh son is one of the conditions that can help someone penetrate a Changeling's glamour.
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