In the Blood



"I am the guilty one Ball and chain around my leg I am the cursed one Black cloud hangin' overhead ''Fill the heart that pumps bad blood All inside of me."

- Jon Spencer Blues Explosion, Killer Wolf

Genealogy and Ancestry are really popular tropes in fiction. It makes a great Secret Legacy, a source of fraternal conflict, adds drama with an unexpected family reunion, and can set up a host of different conflicts and relationships. Just like in real life, a person's ancestry can determine their genes and, to a lesser extent, their personality and even their talents; but in fiction this extends to skills, superpowers, and even moral alignment.

Sometimes even The Messiah and the most valiant Knight in Shining Armor are at risk of going insane, or over to The Dark Side, if a parent or grandparent was a Villain by Default or member of an Evil Race. This inevitably leads said character into a Wangsty existential crisis that comes completely out of left field, since they rarely ever struggled against villainous impulses before this revelation.

The reverse is not always true though. A Card-Carrying Villain with a good family is rarely compelled towards good—though it does inform a possible Heel Face Turn later on thanks to The Power of Love from their family.

The hero's fear in this situation is that their "evil genes" will inevitably doom them to become as evil as their ancestors Because Destiny Says So, it's written In the Blood—despite the fact that up to the point before The Reveal they had a solid reputation, moral compass, and personality, capable of using Heroic Willpower to resist just about any evil supernatural coercion. It seems heroes are as insecure about their ancestry as their reputation.

The inevitable conclusion to all this navel gazing is either the character going "Screw Destiny!" or a friend slapping some sense into them; if he has been raised in ignorance so that he would not Turn Out Like His Father, it is quite likely to actually work. On the other hand, this can end up being a Self-Fulfilling Prophecy, in that the angst leads to fear, then hate, then evil, as the character either does a full Face Heel Turn or becomes Necessarily Evil. For a comparison, the Reluctant Monster bypasses this nonsense entirely and is simply "themselves," albeit with a healthy heaping of introspection.

Now, get an Evilutionary Biologist who thinks the same thing, and they'll try and splice together a clone Super Soldier of the hero using such donors as Hitler, Stalin, Pol Pot, and Scrappy Doo, under the logic that their creation will be "the most powerful and evil creature alive! Bwahahahaha!" Which, of course, should only produce a clone with a penchant for mustaches and Scooby snacks, but invariably is pretty evil.

A pretty common twist for heroes with Muggle Foster Parents is that they are the child of the Big Bad who has been spirited away and raised like an Ordinary High School Student in the hopes that Nurture can beat out their inherently evil Nature. Amazingly, sometimes it's because Evil Parents Want Good Kids. In extreme cases, this "Nature" can manifest as an Enemy Within or a Super-Powered Evil Side. Again, this twist can lead to a Shower of Angst. For some reason, the parent they get the bad blood from is usually the dad. Another twist is the son of a mighty warrior becoming a mighty warrior themselves, even if they were orphaned as a baby.

Sub-trope of Not So Different. See Freudian Excuse for when the Nurture position applies. Compare Lamarck Was Right for children inheriting non-moral traits that shouldn't even be genetic. A big issue for anyone with a Mad Scientist Truly Single Parent. Creates numerous problems if the blood it is in is Royal Blood. The more light-hearted version is It Runs in The Family. Compare Raised by Orcs, where someone raised by evil people/races turns out good due to not actually being related to them and Heroic Lineage from their true parents. Compare Loser Son of Loser Dad, where everyone else thinks this will be the case. Contrast Sibling Yin-Yang, when the same blood give very different results.

Not to be confused with the novel of the same name or the fanfic of the same name.

Anime and Manga

 * In Code Geass, Lelouch vi Britannia has become a rebel trying to overthrow his tyrannical father, Emperor Charles. However, his methods rely heavily on manipulation and devious plans ... just like his old man's own actions.
 * Schneizel, too, shows a great deal of manipulation in his behaviour.
 * To summarise, many members of the Britannian royal family are this, one way or another.
 * In Princess Tutu, Fakir
 * Not to mention that the blood of the Raven will turn people towards evil and give them dark magical powers if it's somehow absorbed by their body, even if they're not related to him.
 * The goddess Urd of Ah! My Goddess is a near expy of her mother, the demon and ruler of Hell, Hild. Even though she identifies as a goddess and it is her affiliation, people have told her more than once her temperament is closer to demon - or rather, nearly exactly like her mother, which is the same for all intents and purposes. This even though she was only raised by Hild for a few early years, and has been a goddess as long as she can remember. Her power is also in the leagues of her mother.
 * Being connected to a criminal by blood seems to be quite a stigma in the One Piece world, mainly from the World Government who are afraid that it really is In the Blood. Nico Olvia separated herself as much as she could from her daughter Robin when she set off to be an illegal Adventurer Archaeologist to try and keep Robin from being the "child of a criminal." When the Franky Family are trying to convince the Straw Hats to take Franky with them, one of the reasons used is "he's the son of a pirate, anyway." Most recently, when Vice-Admiral Garp tells Ace that he'd wanted him and his brother Luffy to become great Marines, Ace tells Garp that their fathers' blood assured they could never be Marines.
 * Averted in Whitebeard's beliefs, though.
 * Actually in spite of the rather crazy lineage of Luffy's family (The marine's hero, the most wanted man in the world, The future pirate king), one of the major themes of One Piece (confirmed by Word of God) is that heredity doesn't matter, and family is who you choose. Of the strawhats, only Usopp grew up with a parent related by blood, and she died when he was quite young. Of Sanji, Zoro, Nami, Chopper and Franky, none had significant blood relative parental figures, Robin only met her mother briefly, We don't know about Brook, and Luffy was raised by his grandfather until he was shipped off to stay with his grandfather's friend. Luffy also rather significantly had a.
 * The Nakama theme becomes much more evident in the Fishman/Mermaid heredity. Either species can give birth to an species each other with no qualms as it just means they must have had some ancestor to inherit it from.
 * The Uchiha Clan from Naruto is the embodiment of this trope with the clan founder, Madara, even saying that.
 * However, there are two subversions: First off, and most notably, Obito, Kakashi's Unlucky Childhood Friend. He acts pretty normal and even clumsy, and the usual Uchiha-appearance is toned down with a ridiculous pair of goggles. Secondly, though not to the same extent as Obito,
 * In fact,  was more or less totally indifferent to revenge. His controlling factor appears to have been a weighted utilitarianism, trying to preserve the greatest possible amount of what he valued, with (excessively) slight adjustments made for innocence. if he cared about revenge, he would have killed Danzou years before the story even started, for putting him in the position to choose between  . He certainly wouldn't have remained a loyal shinobi of Konoha, let alone   before Sasuke even reached his final level of rogue. He was a very weird Uchiha.
 * And now that, he seems to be a fairly equal-opportunity asshole, even if he hates some people more than others.
 * Dragonball Z: While Frieza was a Complete Monster and Buu was in it For the Evulz, Cell was born with no other purpose other than becoming more powerful.
 * Somewhat arguably,  from Yu Yu Hakusho. Though it's not dwelt on much, partly because by the point in the series it comes up things have gotten to be semi-pure action, far far away from the series' roots as a chronicle of the reflective character-building experiences a delinquent can have while a ghost, probably because Togashi had gone mad with power by this point,   Could just be an implicit redrawing of the Fantastic Racism lines, with demons no longer suffering from What Measure Is a Non-Human? because he wasn't human. So it might just be a really strange form of a perfectly reasonable Aesop, and/or Reverse Getting Crap Past the Radar due to not treating it like it's important. Intended to cause Fridge Logic, probably. Altogether weird.
 * Hiei, on the other hand, turns out to be the victim of the idea of this in his back story: being male shows he has outcross blood, which among the Ice Maidens means (precedents apparently show) that if they keep him around he will grow up to kill everyone. So they throw him over the side of their Floating City, the woman doing the throwing whispering that she expects him to come back and please kill her first. They may or may not have been correct: yes, he is a psychopath from childhood, and actually mellows out the more grown-up he gets, and yes, judging by his facial expressions he was one evil baby, but that could be a combination of Self-Fulfilling Prophecy (though come to think of it, it doesn't), the trauma, and the fact that all babies are extremely selfish little creatures and if they were, like Hiei, sapient they probably would be kind of evil. He understood everything. (Of course, the 'source of evil' here is either 'every race except our own' or 'the male sex,' or both, because they don't have males. They clone themselves every hundred years.)
 * Jury is out on Yukina. She may or may not share Hiei's father's blood, and has been known to express genocidal sentiments toward her own kind. Hiei told her that if she wanted them dead she should do it herself, not rely on some imaginary brother who might be dead. Since he'd decided it was crueler to let them live, and all. She considered that movingly positive advice and smiled adorably. She did not so far as we know ever go home and kill anyone.
 * The Ant King Meruem of Hunter X Hunter was born full-grown, intelligent, utterly selfish, and with the mission to conquer the world. Most of his character development as he grew up just reinforced his Blue and Orange Morality Evil, but he eventually, after a few months and under the influence of a sweet little blind girl with a perpetually runny nose whom he couldn't beat at a strategy game, developed into an honorable adult being. Still very cruel and arrogant, but given he was possibly the most powerful thing on the planet it would be hard not to be. Given his mother's attitude and the fact that he presumably contains bits of the sentience of various humans she ate during his gestation, because that's a chimaera ant ability, it's hard to say what can be called In the Blood for him, but he seems to have risen above his nature.
 * He then died of an Expy of radiation poisoning. The reader is generally equal parts sad and relieved.
 * This is part of the reason why it was feared Soul Eater's Black Star would end up on the 'path of a Kishin'; his father ended up destroying himself and his clan. A comparison between father and son is made by Sid, who raised Black Star and played a part in killing the rest of the Star Clan.
 * This is very likely to become a problem for
 * In Eureka Seven, the Thurston family (especially the males) are all well-respected and loved people. Axel Thurston was respected by the military for his design and contributions for the LF Os, Adrock Thurston was remembered by the people for his Heroic Sacrifice to save the world, and Renton Thurston was also known by all for saving the world and became a hero (his name is displayed on the moon for all to see, as well as a street named after him in the ending).
 * Axis Powers Hetalia: insanity certainly seems to be In the Blood for the Soviet family. Also, North Italy and Romano are both weak when it comes to warfare and share their love of food and women with Grandpa Rome. Germany and Prussia both have ambition and a love of power. Ironically, it's never clear how countries reproduce or whether they are actually related, and it's implied that they might actually not be related in the traditional sense, but those who call themselves family do seem to have a lot of traits in common.
 * In the Detective Conan The Phantom of Baker Street Non-Serial Movie, it begins with a social commentary about Japan's hereditary culture but this trope comes around with the revelation that  Basically it could be about how concentrating on erasing mistakes of one's ancestors can make you repeat them.
 * Zig-zagged to hell and back in a short story in Melo Melo Melonpan with Mira being Happily Adopted by a woman and her son, having a secret affair with adopted mom, living a good life until being (re)captured by his biological mother, who used to have him as her personal sex slave until he ran away then does the same with said adoptive family until the adoptive brother kills both her and her mother/Mira's grandmother then goes to find his mother, leaving Mira to raise his inbred daughter and aunt as his Morality Pets to rule the kingdom justly... only to learn said Jerkass behavior runs in the female side of the family, doing the exact same things to him until he commits suicide, leaving the kingdom in the hands of two pregnant, inbred Royal Brats. Damn.

Comic Books
"Professor Zoom: Your mother may be a Thawne, but your father was an Allen. Your blood is polluted. Bart: Look on the bright side, Professor Plum. We're only half related!"
 * Orion, son of Darkseid. Orion's a good guy, but he inherited Darkseid's inherent rage and bloodlust, and requires a Mother Box to keep his temper in check.
 * In the DC Elseworld Kingdom Come, Orion has deposed Darkseid and taken over Apokolips. Apparently he tried to institute a democracy and positive change, but the people just elected him dictator and didn't participate in changing anything, so he's ruling hell and says that "all men eventually become their fathers." He seems resigned to being Darkseid. Only without the universe-conquering ambitions, so that's something.
 * Scott Free, Mr. Miracle the escape artist superhero, is the son that the High Father who raised Orion traded to Darkseid in exchange. He was raised with the other children of Apokolips under Granny Goodness, but he and his Apokoliptan girlfriend, Big Barda, broke out. It's hard to say how much of a factor his New God blood was, but that he developed a coherent sense of morality under Granny's regime probably has to be attributed there.
 * Scott and Barda are working among the groundlings, trying to raise awareness in Kingdom Come. Superman gets them to come build a superpower-proof gulag in the nuked remains of what used to be Kansas.
 * In Teen Titans, Superboy fears this after discovering Lex Luthor is one of his genetic fathers. It worsens to the point of a Heroic BSOD when it turns out that Luthor had implanted the ability to control him, and forced him to attack his friends.
 * Robin points out an even worse possibility than becoming evil: "You could go bald!"
 * Titans also has an actual example in Raven, who spends much of the 90s evil, due to her demonic heritage.
 * Even though she was supposed to have purged that after the very first story where it came up, apparently it's so cool and Evil Is Sexy Stripperiffic she just can't shake it. Made even worse by outside parties like her father (who can still cause problems even when dead), a cult that worships her father, and her own half-siblings who try to enforce this trope.
 * This is a legitimate worry for the Runaways at first, before they decide to Screw Destiny and stick it to their parents.
 * The comic version of Wanted features the character Shithead (a Captain Ersatz of Batman villain Clayface), made of the feces of the 666 most evil people in history. Also, Complete Monsterhood runs in Wesley's family, since his father was an equally depraved supervillain.
 * Used in Spider-Man and Spider-Girl, with the "Osborn Legacy" ending up twisting three generations of Osborns. There's no evidence that any of them were evil before Norman, and even if his formula affected his genes, Harry was already a teen at that point.
 * Harry's son Normie, however, turns out to be an Ineffectual Sympathetic Villain, and gets better real quick.
 * One story suggested Norman's father wasn't a terribly nice man; he may not have worn a funny costume, but he had the same obsession with "a strong heir" that Norm inflicted on Harry.
 * This link explains the whole story of Norman Osborn, and how he became the monster we all know and fear. And it proves just how evil Norman Osborn's father really was.
 * In X-Men, the Lensherr/Eisenhart/Maximoff/Da—Oh, hell, Magneto's family seems to have a lot of issues with this. The man himself tends to go mad fairly regularly, Scarlet Witch was responsible for Avengers Disassembled and House of M, Polaris also seems to spend half her time as an evil lunatic, and Quicksilver (getting off more lightly than the others) went kind of crazy after getting his powers back following the decimation.
 * Still not the first time Quicksilver's gone crazy.
 * For an example of someone who doesn't give a second thought to their villainous ancestry, look no further than Bart Allen—better known as Impulse/Kid Flash II. It's common knowledge that he's the grandson of the Silver Age Flash. What isn't common knowledge is that he's also descended from Barry's psychotic Evil Counterpart, Professor Zoom. He's long known this fact, but doesn't really think about it, let alone talk about it, unless someone explicitly brings it up, and more-or-less laughs off Zoom's accusation of "bloodline betrayal":


 * Captain America (comics) has two examples. Helmut Zemo, son of Heinrich Zemo and Sin, son of The Red Skull.
 * Somewhat averted by the Red Skull himself, who takes to having had his mind transferred into a clone of Captain America's body by Arnim Zola like a fish takes to water and is never seen to worry about literally having his idealistic enemy's blood now somehow "weakening" him in any way.
 * Helmut's tended to avert the trope as well, especially since he founded the Thunderbolts. He's still a Manipulative Bastard with a serious mad on for Captain America, but he's not the Complete Monster that his father was.
 * Doctor Strange's girlfriend Clea has avoided this. She's the daughter of Umar and the niece of Dormammu and she's still on the side of good.
 * Mad Scientist's Beautiful Daughter?
 * Vandal Savage's daughter, Scandal, usually seesaws between Anti-Villain and Anti-Hero, though that's a lot better than her father, who's pretty much a fulltime villain. It's plausible that without her father's interference, she could have become a normal young woman or a heroine.
 * In Hellboy, Hellboy himself is the son of a demon prince but is a good guy in spite of his pedigree. The various other demons he meets are all convinced that he should be allied with them, and will make a Face Heel Turn eventually. Hellboy himself is initially dismissive of the idea, but has become increasingly worried that there may be some truth to this. It's also played rather more literally than most examples: in "The Island", a man drains HB's blood and uses it to reanimate himself, and the blood causes the man to transform into the demon Hellboy "should have been". He also steals his crown and his name, which Hellboy then uses as a weapon.
 * Apparently he is also, through his mother, the first male descendant of King Arthur since Mordred. Morgan Le Fay is backing him as King of England. Certain members of the English nobility heard about this before he did, were less than pleased, and lured him out on a giant hunt so they could stab him In the Back. They were then killed by giants.
 * Please note that this story is set around the turn of the 21st century; Hellboy was born on earth in 1945.
 * Stephanie Brown and, to a lesser extent, Cassandra Cain sometimes get this treatment from Batman because of their parents being supervillains. It depends on the writer. While Cassandra occasionally struggled with this thinking early on due to some issues she had, Stephanie never has, likely because the impetus for her superheroics was to spoil her father's criminal ambitions.

Film
"Mr Big: Make my coffee extra strong. Action Fighter: I also take my coffee...extra strong! Asian Sidekick: It is as foretold in the prophecy!"
 * Star Wars plays with this, Luke's Final Temptation to join The Dark Side hinges on him being his father's son and heir to his evil. Luckily, he inherited a few traits from his mom too.
 * It was also implied, in A New Hope, as being his aunt and uncle's reason for never discussing his father with him... or at the very least telling Blatant Lies. (Spice freighter navigator my ass!) They feared that Luke would become a Jedi, like his father before him, and go gallivanting across the galaxy to turn evil That, or just get killed - it's never stated just how much Obi-Wan told them about Anakin. The two always told Luke he'd died offworld.
 * Dark Empire has him turn to The Dark Side when the Emperor returns, in an attempt to bring him down from within. It doesn't exactly work. The parallels with Anakin are made blindingly obvious, though the comic came long before the prequel trilogy. Luke guides a ship far too large and damaged to land into a survivable landing on Coruscant. He constantly ruminates on his father's legacy, wondering why he had turned - ultimately it's the threat to his family that gets him to claim "My father's destiny is my own." The Emperor proceeds to replace his mechanical right hand with a different prosthetic, a "better" one speculated by some fans to be of a model Vader used, and dresses Luke in outfits clearly inspired by his fathers', as can be seen in the page image. Ultimately it's the love of his sister, and his refusal to hurt her or allow her to be killed, that brings Luke back.
 * In the Expanded Universe, his GRANDSON turns for this reason, more or less.
 * A History of Violence uses this when Tom's son, upon discovering his father, abandons his earlier pacifist stance and brutally beats up a bully (who he'd previously handled with wit), having "inherited" his father's violent fighting style.
 * Used for comedic effect in Children of the Revolution, a black comedy about the illegitimate son of Joseph Stalin, who ends up starting a totalitarian communist revolution in Australia without ever being informed of who his real father was—even going so far as to grow the "Stalin mustache."
 * In Young Frankenstein, the titular Dr. "Fronkensteen" tries to avoid following in the footsteps vootshtaps of his famous relative. He can't, if only because the servants won't let him.
 * The Doom movie uses Genetic Engineering Is the New Nuke this way. The Precursors of humanity living on Mars developed a new chromosome that wiped out disease and made them super human... or super evil (You can guess what wiped them out). Apparently the chromosome reacted to the something in the "unmapped 10% of the human genome" that unlocked a person's latent "evil" and mutated them into a monster; the best these gentically evil people can hope for is a Heroic Sacrifice before they fully mutate. So Rousseau was wrong, technically people are genetically evil, and all it takes is a little help from The Virus to bring it out.
 * The forever brutish Tannen bloodline in the Back to The Future movies. The line goes back to "Mad Dog" Tannen, a murderous Wild West outlaw who kills Doc Brown in one timeline. In 1955, Biff Tannen is a bully who tries to rape Marty's mother. In various timelines, he matures into an abusive boss, a crime lord, and a bitter old man. Biff's grandson is a monstrous thug.
 * Jack Sparrow tells Will Turner in the first Pirates of the Caribbean movie that "Piracy is in your blood," since his father was also the pirate "Bootstrap Bill" Turner. Later on it turns out to be an important plot point, and Will embraces his pirate heritage. Of course, no mention is made of whether Bootstrap Bill's father was a pirate. One pirate parent is apparently enough to turn his heirs into pirates as well.
 * Aragorn in the film version of The Lord of the Rings has deep seated fear he will prove to have "the blood of Isildur" and choose to use the One Ring, which extends to him being fearful of taking up his mantle as king. Still, the Ring has a rather good track record on the whole evil tempting and corruption thing, so it's not like he's inheriting weakness so much as not inheriting super resistance to its influence.
 * Not exactly the case, as there's a true genetic component there, he's not purely Man, he's got Elven blood in the mix, which accounts for his superior attributes such was longevity (he was 87 at the start of Fellowship, and lived to 210).
 * From the 1999 movie Wing Commander, Pilgrims.
 * In Repo! The Genetic Opera, this is used in a more literal sense—Marni died from a rare blood disease, which her daughter, Shilo, inherited. 'Genetic Emancipation' is also based on this trope,
 * Also played with in a figurative sense when
 * In The Bad Seed, Rhoda is the granddaughter of a serial killer and has genetically inherited the inability to feel guilt.
 * Serial Killer Mr. Brooks worries that his daughter has inherited his homicidal urges.
 * Parodied lots in Tongan Ninja, with the evil Mr Big and his long-lost son, Action Fighter:


 * Freddy Krueger's great paternal linage helped make him the great man he is today. Yup all 1000 of his psychotic inmate fathers.

Literature
"Before I open this envelope I am going to tell you what I believe it contains. I have not the slightest evidence except personal conviction, but I believe that the paper inside this envelope is written by my father's hand and I believe it tells me that he was not Eileen's father and that I am not her sister. If it does not say this, then there is nothing in race and blood and inherited tendencies.""
 * The work of H.P. Lovecraft. From Shadow Over Innsmouth's protagonist to the protagonist of The Rats in the Walls having a predisposition toward ; this is not to mention The Tomb's family links between the dead and living, it's completely pervasive.
 * Also check out the late Arthur Jermyn.
 * Imriel in the Kushiel's Legacy books is the son of the biggest traitors to his country, and despite him being a good-hearted person (and raised by other goodhearted people), everyone around him suspects that someday he might take after his mother.
 * Played with in A Song of Ice and Fire: The Targaryen royal family line is known to be "tainted" with madness; one character says that every time a new Targaryen was born, the country would hold its breath to see if the new Targaryen would be one of the good ones or one of the bad ones. However, this is Justified Trope. The Targaryens are seriously inbred due to repeated Brother-Sister Incest; the inbreeding results in many of this line having physical problems and/or serious mental and emotional instability, while the luckier ones inherit the family strong points and manage to miss the damaging recessives.
 * Also,
 * Averted in Good Omens. The Antichrist, through a variety of mix-ups, ends up being raised by a normal British family. He ends up like a normal kid with some special powers he's only partially aware of. Even his hell hound ends up being like a normal dog, though with some worry on its part.
 * They address this trope directly at one point, with Crowley pointing out that Lucifer was originally an angel, so the idea that Adam is destined to become evil due to demonic genetics is absurd. Incidentally, in this story demons and angels even have identical wings; falling from grace just changes what team you're playing for.
 * All over the place in The Kite Runner, as: Hassan's son is said to be very much like him, which plays this straight.
 * Played straight in the Redwall series, where certain species are always designated as "good" or "bad." Even when a ferret (one of the "vermin" species) named Veil is raised from infancy in the abbey, he ultimately turns out to be evil. "The goodies are good and the baddies are BAD, no grey areas." (Weirdly, cats are one of the few species that's an exception to this rule, being good or evil—in a series where mice are the standard heroes.) There are occasional exceptions, with good-aligned "vermin species" or evil-aligned "good species" but they are few and far between.
 * Understandable as this is a kid's series. Kids don't really understand 'grey' so much as they do 'GOOD' and 'BAD'. However, this is not a good thing to teach kids.
 * The entire plot of Wilkie Collins' 19th-century thriller Armadale revolves around this trope; a young man who has (for unrelated reasons) adopted a pseudonym meets another young man who shares his birth name of Allan Armadale. They become fast friends, until the first young man discovers that his father had murdered the father of the other Allan Armadale. He spends much of the rest of the novel haunted by his father's conviction that the sons are destined to repeat the fathers' fatal feud.
 * In The Count of Monte Cristo, Benedetto is supposed to be a bad guy because of the evil inclinations of his father Vilefort. Adding to the Unfortunate Implications is that like Oliver Twist (and likely many other orphans in 19th century novels), he is naturally educated and well-spoken, despite receiving little schooling, simply because his father is an aristocrat.
 * In Arthurian literature, Mordred, the born-by-incest, sometimes-tragic nephew-son of the King, is a villain BECAUSE his parents consummated in sin. This is often the reason for the fall of Camelot as well. And Despite that in the original Welsh legends had Medrawd as a hero and unrelated enemy of Arthur's, with Arthur as the villain, and the incest originated in the Vulgate Lancelot-Grail Cycle.
 * In P.C. Hodgell's Chronicles of the Kencyrath series, Shanir (magic) powers are inherited genetically among the Highborn race. Incestuous breeding programs in the past to breed stronger Shanir have led to some very damaged bloodlines, exacerbated by dwindling numbers (and probably causing them, too, due to impacts on fertility). Heroine Jame and her twin brother Torisen are of the "royal" house of Knorth, inheriting both powerful abilities and the possibility of insanity; Torisen constantly worries that he carries the Knorth madness and worries he'll become his father. One of those abilities is also In the Blood; blood-binding. Anyone who consumes their blood will be bound to them mind, body and soul until death and beyond. Creepy stuff.
 * The Dark Elf Trilogy: Drizzt Do'Urden seems to get a break from the drow characteristic of being Exclusively Evil because his father is an exception, too. Of course, this also affected his upbringing, but there's a sense a "biological" excuse is seen as necessary.
 * Interestingly, some other drow are implied to have had the potential to be good, but to have lost it due to the lives they've lived. Drizzt's sister turned evil due to their mother's influence, and Jarlaxle (who isn't even from Drizzt's family!) demonstrates what Drizzt observes as an odd sort of sanity for a drow, despite being a ruthless mercenary. Given Mooshi's comment that the children of evil species often demonstrate "not-so-subtle differences" from good races, a mutation is looking more and more probable, albeit a mutation that's struck more than one family line. Of course, he's also son of Yvonnel, and she lived to the respectable age of 2043 not by doing things For the Evulz when it's bad for business - the House Baenre got its status because she was the one who said "stop this foolishness" when Menzoberranzan began descent into open infighting the first time. Of her other children, we know Gromph, who also lived to his age not on the reputation of his family, and Quenthel, who can compete in creative cruelty with the best of 'em, but in War of the Spider Queen managed to throw off Stupid Evil mind control because such un-Pragmatic Villainy as going Ax Crazy was against her nature.
 * In the Middle English Chivalric Romance Sir Gowther, the title character is the son of a devil (the same devil who begot Merlin). He kills several nursemaids by suckling them to death, then grows up as a naturally horrible person who eventually goes so far as to lead a gang rape of a convent full of nuns whom he then locks up and sets on fire. However, when someone actually tells him that he is the son of the devil, he repents immediately, goes to the Pope for penance, and eventually becomes more or less a saint.
 * Merlin himself is alternately an example and an aversion of this trope. In some medieval texts, he inherits his incubus-father's powers and his evil or amoral nature; in others, he inherents the powers but not the evil, and he receives some powers from God as well.
 * Played horribly straight in Gene Stratton Porter's 1904 novel Freckles, in which it's accepted by everyone—including, too obviously, the author—that an abused child must be unworthy of compassion, because it is the offspring of Abusive Parents. The hero turns out to be a good and decent and upright man, of course—precisely and specifically because his parents were all those things.
 * Sherlock Holmes speculates that the reason Colonel Moran from "The Adventure of the Empty House" started out as a fine, upstanding soldier of the Empire and then suddenly joined the Moriarty gang might be because "the individual represents in his development the whole procession of his ancestors, and that such a sudden turn to good or evil stands for some strong influence which came into the line of his pedigree. The person becomes, as it were, the epitome of the history of his own family." Watson calls this "rather fanciful".
 * In another case, Holmes deduced that a nice-seeming man was a closet Complete Monster because his young son was cruel to animals. While this isn't an implausible deduction, Holmes attributed the boy's misbehavior to this trope rather than to the trauma of abuse at his father's hands.
 * Captain Pausert in The Witches of Karres had to listen to Councilor Onswud saying he'd known Pausert would go bad (as Onswud saw it), "Just like his great-uncle Threbus! It's in the blood, I always say!" And then Threbus' daughter told Pausert her father had predicted Pausert would break with his home planet—and he said it was in the blood.
 * Averted with the The Sword of Truth.  Rahl spends several books explaining that he's nothing like Darken Rahl. It turns out that way back when, the Rahls were some of the champions of order and good, but were corrupted by several thousand years of uncontested rule.   takes after the parents who raised him, not his genetic ancestors. However, there are Rahl traits - like arrogance, determination, cleverness, and absolute ruthlessness, that the character in question develops over time.
 * An issue in the Wheel of Time - one of the protagonists was adopted, but was assured that he is considered the son of the one who raised him. His genetic family does still take him in, but that probably also has something to do with him being.
 * It turns out that the ability to touch Saidar or Saidin is inherited ... and the Red Ajah has been culling male channelers because they go insane and kill everyone in their general area. Oops.
 * Inverted in Mark Billingham's novel "Bloodline", in which the descendants of a notorious serial killer's victims are being killed off one by one, then later played straight when it is revealed that
 * In The Belgariad, Urgit, King of the Murgos, believes he will go insane like his father Taur Urgas did because the Urgas dynasty is plagued by hereditary insanity.
 * Near the end of the North and South trilogy, the recurring villain (and increasingly Ax Crazy) Elkanah Bent is revealed to have been conceived when his mother's father raped her. Upon learning this, another character freaks out and ends an inner monologue with ".,his blood, his brain poisoned by his birth."
 * Older Than Feudalism: Played straight and averted in The Bible. All humans end up inheriting original sin and death from their ancestors Adam and Eve. Averted with Abraham and David, where God makes a covenant with them to set up a nation and monarchy, respectively, with their descendants hoping that they will be as faithful as their ancestors. Save for a few notable exceptions, he turns out to be dead wrong.
 * In After The Golden Age
 * The blurb to each of the three Kaywana books goes on and on about how the tainted blood of the van Groenwegels drives them to evil.
 * In Gene Stratton Porter's Her Father's Daughter, Linda receives a direction to a letter when she turns eighteen. However, blood had told before then.


 * Madness seems to be a family trait for the Angelfields in The Thirteenth Tale. George, Charlie, Isabelle, and the twins are all off.
 * Invoked in the BattleTech novel Star Lord. The eponymous character, a distant descendant of Stephan Amaris (the man whose actions brought down the Star League and incidentally proved him to be a Complete Monster), decides upon discovering his legacy that it must therefore be his destiny to step into his ancestor's footsteps, topple the Great Houses of the Inner Sphere, and take over himself. He's unambiguously crazy, but wholeheartedly embraces his belief and proves charismatic enough to attract a number of down-on-their-luck followers to stir up trouble for him.

Live-Action TV

 * Law and Order Special Victims Unit: A recurring fear for Olivia Benson is that deep inside her is a violent, sadistic criminal spawned by her rapist father. John Munch has also voiced concern at least once that he may end up committing suicide like his father. There was also an episode where a man who was violently molested by his father worries about becoming just like him and his felon brother—and does so.
 * Note that Munch's fear isn't entirely unreasonable: his uncle Andrew (played by Jerry Lewis in an episode) had mental problems, and that sort of thing, which can result in suicide, can be heritable. Goren on Law and Order: Criminal Intent has the same concerns due to a family history of schizophrenia.
 * Also, Olivia went through a very complicated situation where it seemed her fears her coming true...
 * There's an episode of the original Law and Order ("Born Bad") where a teenager on trial for murder has his parents put this forward as a legal defense - due to a unique genetic condition, the teen is predisposed to a life of violence, and thus not wholly responsible for his actions.
 * Supernatural's Sam Winchester develops psychic powers slightly before the start of the show, which eventually turn out to come from their family's demonic nemesis having fed Sam his own demonic blood in the cradle. Fear about destiny and inevitability increase as more and more of the other children so marked go 'darkside,' or in one case kill their psychotic brother who had, and their father's final words to Dean are that if he can't save Sam, he may have to kill him. Sam resists the original 'destiny' associated with this status by not killing during the demon's little Battle Royale, but the other survivor opens the gate to Hell anyway.
 * Later, after he developed his powers further by drinking more demon blood to exorcise demons so he could prevent the Apocalypse and became addicted, it turned out that he'd been being prepped for years to open a different door.
 * This gets treated as In the Blood despite it just being a few drops of ingested liquid rather than actual heredity. Of course, once it turned out their mother Mary sold Azazel the right to take 'something' from her house in ten years, and that in cases where he wasn't interrupted no one was killed or kidnapped, it seemed the demon did in fact have the rights of a parent over the kids he'd bought, and the blood thing was claiming that and preparing them to open the doors and enable the endgame. Presumably he was only in charge of opening doors, given that Sam was the favorite but not necessary to his understanding of the endgame, and chance or destiny or Lilith arranged the rest.
 * Destiny also grabbed the Winchesters by the veins in that they are apparently descended on both sides from a line of archangel vessels, and were born to house Lucifer and Michael for their final apocalyptic battle on earth. Lucifer says, "It had to be you, Sam. It always had to be you." Presumably,the Campbell line was Lucifer's vessels and the Winchester was Michael's, and the reason they had to bring the two together in John and Mary was that the final vessels needed to be brothers. Lucifer's lack of interest in Adam and Michael's in Mary might point this way, but it's not conclusive. The idea of destiny is thrown about a lot here, but given how hard Heaven and Hell both had to work to make it happen, Destiny may just mean 'the plan.' See also, The Call Knows Where You Live.
 * There is an in-universe procedure for breeding actual half-demon children. The one who turns up in season five is apparently the Antichrist, a decent little kid named Jesse with enough power to hypothetically threaten the Heavenly Host. The Winchesters talk to him a bit, borrowing help from Spiderman, and the kid becomes an Anti-Anti-Christ by running away from home and vanishing so he couldn't be used in any war, despite the fact that he could have saved the world from many of its major threats since and might be a major resource against the Leviathan in the current storyline. In the Blood apparently defied here.
 * Holling from Northern Exposure didn't feel he should ever have children because every Vincoeur from the cruel French aristocrats down to Holling's foul-tempered father had been some sort of sadistic monster. Holling himself was a perfectly sweet and kind person, and didn't seem to fear turning into a jerk himself—but at the same time was convinced that the vileness would carry over to his kids should he ever have any. (In fact, one child of his did turn out to be a money-grubbing con woman.)
 * Chouseishin Gransazer has a lot of hand-wringing Wangst near the end when it is revealed that
 * That's just chemistry. When it gets to the metaphysical, people take the moral implications a lot more seriously. Which makes sense, since the metaphysical is generally a moralistic construct, so if it's real....
 * A more realistic version of this was done in Smallville, where Chloe is afraid she'll end up like her mother. But it's not evil, it's insanity, which often is genetic. Lex on the other hand, has evil genes, although the nurture side isn't helping either.
 * Clark himself believed this of "Luthor blood", until the episode "Luthor" where he discovers that his alternate self, raised by Lionel Luthor, was monstrous as an actual Luthor even without the blood relation. This realisation allows him to accept that Tess Mercer, the biological daughter of Lionel Luther, can be trusted to be a subversion of the trope.
 * One of the main sources of dramatic tension in American Gothic is the question of Caleb's parentage—not just whether he really is Buck's son, but whether he can actively resist becoming corrupt and evil just like his father. And it seems he and Merlyn are right to worry, since . Of course this is likely helped along by his near-death experience, Buck's powers, and but the simple fact is after ten or so years of showing no signs of evil, once he learns of his (possible) heritage, Caleb's fall into darkness is somehow inevitable.
 * Towards the end of the epic miniseries Centennial, the evil Wendell clan comes along. Perhaps we can blame them for how the quality of the series really started to deteriorate around that point.
 * The Avatara in Carnivale get their powers and Dark or Light natures genetically. Siblings of the Avatara, called Vectori, are said to have minor abilities of their own and tend toward insanity.
 * On Criminal Minds, the profilers always debate the possibility of a serial killer's offspring growing up to be like their parent whenever one of them is revealed to have kids. Justifiable discussion, since Psychopathy is suspected to have mainly genetic predispositions, whereas Sociopathy mainly environmental. Of course, not all people predisposed to become Psychopaths become such, and not every Psychopath becomes a Complete Monster and/or Serial Killer.
 * Spencer Reid worries a lot about becoming a paranoid schizophrenic- like his, as there is a higher chance of it occurring in him if a family member also has had it.
 * In "Birthright", a man who never knew his father found his journal detailing his killings and decided to become his copycat.
 * Averted by the wife of a serial killer who was on death row for killing her infant son to prevent him from growing up with the Awful Truth about his father Even the BAU decides she did the right thing in the end even if they wouldn't have made the same choice.
 * Langston in CSI assures
 * In the Bones Season One finale, The Woman in Limbo, upon learning that, Russ Brennan, a felon on parole, says "Guess a criminal nature runs in the family."
 * Inverted humorously on Top Gear, in an episode featuring the presenters' mothers. While some personality influences are obviously present, Jeremy Clarkson and Richard Hammond's mothers are slow, careful drivers, and James May's is remarkably aggressive and fast.
 * Justified does not state this trope but is highly influenced by it. Raylan shares a lot of character traits with his father Arlo and does not want to be an angry, violent manipulative bastard like him. The show likes to show how much alike the two of them are even though one of them is a good guy and the other a bad guy.
 * This trope is twisted all around with the Crowder family. The patriarch Bo is a brutal career criminal who easily steps into Complete Monster territory. Boyd is a villain from the beginning but is revealed to operate on very different motives then his father and Bo Jr was a star football player and thought to have a great future but ended his life as a wife beating brute whose own family did not feel like avenging. Cousin Johnny is first shown to be the one who has gone straight but in the end is just as bad as his uncle Bo.
 * The Dukes of Hazzard has a number of examples in relation to the Dukes: They've been making moonshine ever since before their ancestors came to America. They've been "fighting the system" for as long as the Duke Clan and corrupt politics have coexisted. In the old west, the Duke's ancestors displayed an affection for fast horses; in modern times, they prefer fast cars. The Dukes' ancestors have also been allied with some other clans as far back as those clans have coexisted; this sometimes leads to Uncle Jesse recruiting the descendants of those clans as modern day allies by reminding them of that fact.
 * Boss Hogg and Rosco's ancestors in the old west were also shown to be corrupt.
 * Knight Rider has this with the newer series being a continuation of the old series, and the new Michael Knight being the son of the old Michael Knight. The fact that "Knight" is an alias used after each was supposedly killed also qualifies.
 * The new KITT and KARR also qualify, having been built by the same man as the originals. They reprise the rolls of their namesakes, with KARR being psychopathic and having killed people before being deactivated and supposedly destroyed (but actually just put into storage).
 * The new KARR even shares The voice of his namesake from the origional.
 * The new KITT and KARR also qualify, having been built by the same man as the originals. They reprise the rolls of their namesakes, with KARR being psychopathic and having killed people before being deactivated and supposedly destroyed (but actually just put into storage).
 * The new KARR even shares The voice of his namesake from the origional.

Music

 * Jeff Buckley was raised as Scotty Moorhead by his mother and stepfather. He hardly knew his father Tim Buckley, only having met him once when he was eight. When Tim died in 1975, Jeff found out who he really was and decided to go by his real name. Not only do Jeff and Tim look similar, they both played folk music (to some degree) and died young. Although their music isn't really similar, Jeff's success has been enough to make Tim Buckley much more popular than he was when he was alive.
 * This is the whole point of Amanda Palmer's song "Runs In The Family."

Professional Wrestling
his father]]
 * Just try to find a second- or third-generation wrestler whose gimmick doesn't center around wrestling being In the Blood, face or heel. Probably the best example is WWE's Randy Orton, a third-generation wrestler who believes that his lineage automatically makes him the greatest wrestler ever (never mind that dad, grandpa, and uncle Barry were all midcarders at best...). Orton went on to found a Power Stable called Legacy, where the biggest entrance requirement was that you must be at least a second-generation wrestler. Their motto? "Born better."
 * The Rock's first gimmick in the-then WWF was of Rocky Maivia, the name being a combination of his father, Rocky Johnson's name and his grandfather Peter Maivia's surname. Initially he was pushed as a face but people hated him. After he joined the Nation Of Domination and later became The Rock, he became one of the most popular wrestlers of all time, so popular that he was able to retire from wrestling and has had a successful movie career. His ancestry has paled in comparison to his success.
 * Though not directly descended from a professional wrestler, Rey Misterio started off as Rey Misterio Jr. He is a second-generation wrestler as his uncle (Rey Misterio Sr.) was a successful luchador. This is rarely brought up other than mentioning that Rey is a Mexican icon.
 * This example is a little more successful in Mexican Wrestling, where second generation wrestlers like Hijo del Santo and Perro Aguayo Jr. are huge idols in their own right. They do play this trope straight, with Santo always trying to be the "hero" his father was and Perro Aguayo having many of the same [[Heel Face Revolving Door storylines as

Tabletop Games

 * Used extensively in Warhammer 40,000. The God-Emperor of Man created the twenty Primarchs, and when each wound up being raised on an alien planet by whoever happened to stumble across them, each become an immensely skilled warrior, and most of them ruled a planet or ten. The modern-day Space Marines are all genetically modified with gene-seed based on one of the Primarchs, and all exhibit behavior similar to that Primarch - the Blood Angels and their descendants, for example, all tend to be pious, noble, and prone to turning into [literally] bloodthirsty kamikaze maniacs intent on ripping the enemy limb from limb and drinking their blood.
 * The Tyranid genestealers use this trope as their means of infiltrating other races. They implant their victims with Tyranid genetic material which subverts the genes of the victims. The victim's children are born as hybrids and become genestealer cultists by default.
 * The Space Marines, however, are subjected to extreme hypnosis and mild brainwashing at the same time as they receive the gene-seed. This is mostly to make sure all their implants work, but the result is that they end up more like their Primarchs than when they started—and they were selected in the first place due to their similarity.
 * The descendants of extra-planar creatures in Dungeons & Dragons tend towards the alignments of their forebears. Thus, half-celestials and half-fiends are almost guaranteed to be good and evil. Their descendants, aasimar/deva and tieflings, are also predisposed (though not guaranteed) to maintain their ancestors' alignment.
 * Half-orcs, no matter how civilized their upbringing, favor the barbarian class (especially in 3rd Edition), apparently inheriting the Orc's wild nature.
 * The offspring of a Generally Chaotic Good Nymph and a Always Lawful Evil Devil is a Neutral Evil, misshapen, goat legged midget called a Forlarren. They typically befriend the party with tales of their tragic past but the evil inherited from their Devil father(Its all but stated that they're a result of rape) causes them to murder a member of the party.
 * Exclusively Evil is at least slightly subverted however because "Always" doesn't actually mean "Always". Even a demon, who has pure Evil as part of their very substance, has a non-zero chance of not actually being evil. We're talking maybe 1% who are Neutral, and 0.1% who are good, but it does explicitly happen (though they are still made of Evil, and can be affected as such by spells). This has led to endless debate among players over whether or not this makes beings who the books say are "always evil" okay to kill on sight, even with the slight chance that they don't live up to their stat-blocks.
 * The Book of Exalted Deeds (basically a handbook for being Good) says that killing them is wrong, but also points out that if the DM pulls a bait-and-switch too often by having monsters the players have been merciful to betray them, its understandable that they will be upset and less trusting in the future.
 * Birthright all rotates around bloodlines (duh) carryng little portions of lost godly powers.
 * The Ravenloft supplement Legacy of the Blood uses this trope extensively.
 * Champions supplement The Blood and Dr. McQuark. The Blood have a hereditary tendency to both superpowers and insanity, the result of a bargain one of their ancestors made with a demon.
 * In Hunter: The Vigil, the Lucifuge all believe they are descended from Satan/Lucifer/Beelzebub/whatever name you want to tag the Devil with today. They've decided to Screw Destiny and fight against the creatures of the night... using the powers of Hell. Problem: the later World of Darkness book Inferno introduce their cousins, Les Enfants Diabloque, who also believe they're descended from the Devil and like it. The two groups are at odds.
 * The Shadows of Mexico setting for Vampire: The Requiem portray the Daeva native to that region, called Xoxocti, as priests of the gods. Thanks to centuries of foreign influence, their present day childer don't care about the old ways anymore. Instead, they use their vampiric powers to become sexy Latin pop stars, forcing their ancestors to view them as the children of kings who've been screwing whores. This Cultural Posturing is actually a large part of the setting's plot.
 * On the rare occasions the Created have true children rather than reproduction through reanimation, they're likely to be immune to Disquiet and the illusion of humanity Prometheans automatically project. The kid may grow up somewhat skewed by a childhood of seeing reanimated corpses hanging around, but when word gets around that there's a human they can talk to without said human going Torches and Pitchforks, Junior will have plenty of protectors.
 * "Wolf-blooded" descendants of Werewolves and humans in Werewolf: The Forsaken are immune to the lunacy most mortals experience when they see a transformed Forsaken. They also have a good chance of producing werewolf children with another wolfblood or a full werewolf, making them prized as mates.
 * At least one branch of the Liao family ruling the Capellan Confederation in the BattleTech universe is all but canonically predisposed towards eventually going megalomaniacally, bat**** insane. This may or may not have started with Maximilian Liao, definitely affected his daughter Romano and her daughter Kali, and even her son Sun-Tzu, who is otherwise a Magnificent Bastard, has had cause to worry about his own sanity. (Interestingly, Maximilian's other daughter Candace and her descendants aren't similarly afflicted, definitely suggesting an actual genetic component that she simply didn't inherit.)

Theatre

 * One of the dramatic tension elements in Arsenic and Old Lace is the hereditary insanity suffered by every single member of the Brewster family, and the protagonist's fear that he will eventually succumb to the same madness.
 * Cyrano De Bergerac: Even When Cyrano reacts with shock at Roxane's intention to remain with them during the battle, and she responds, "Monsieur de Bergerac, I am your cousin." lampshades this in a positive context, Cyrano and Roxane's obsessions and denial of reality fit them better with the sinister implications of this trope.

Video Games

 * In the game Dracula, the main character must find her father, a doctor at a sanitarium who has gained some kind of supernatural power, causing him to go batshit insane and slaughter apparently everyone in the hospital and reality warp the living shit out of it. It is eventually revealed that he is a decendant of Dracula, and has lost his mind thereby.
 * If the sequel D2 in any indication, though, she took it pretty well.
 * This trope is played straight in the Baldur's Gate series in regards to the main character and several of the villains, who are.
 * This could just be selection bias, though; the evil have been busily killing off the good ones, and the good ones are less likely to appear on the PC's radar in any case. The PC him/herself can be a solidly Lawful Good Knight in Shining Armor if the player so chooses. In Throne of Bhaal you meet several "lesser Bhaalspawn", quite a few of whom seem to be just regular Joes.
 * Tohno Shiki of Tsukihime lived most of his life normally, yet can somehow instinctually remember all the assassination techniques of the Nanaya clan through his blood, which conveniently powers him up whenever something serious happens. Judging by appearance, you might as well call it his Super-Powered Evil Side. Explained in Canon by the fact that.
 * Being another member of the Demon Hunter's Association, the Ryogi family's daughter also received powers from supernatural blood.
 * Agent 47 from the Hitman series is a genetically engineered assassin, created from the DNA of 5 of the world's most dangerous criminal masterminds. Except he's a cold-blooded assassin, not a power-hungry megalomaniac, so the analogy doesn't seem to quite work out.
 * The plot of the Assassin's Creed series run on this trope—the gameplay is literally In The DNA, a lineage going from Altaïr Ibn La'Ahad ("Eagle, Son of No One") to Ezio Auditore da Firenze (Ezio derived from a Greek word for Eagle) to Desmond Miles. Later implied to be literal, as, partially since Altaïr's bloodline are the only Assassins known to use the ability of Eagle Vision in the games, though Project Legacy revealed that also had it too.
 * The Overlord's son in Overlord2 has the same tendency towards magic and creepiness as his father even before the minions show up.
 * It probably has as much to do with nurture (or lack thereof) as nature, but  is at least as great a petty, murderous Complete Monster as   in Ace Attorney: Trials and Tribulations. Fortunately it seems to have passed over.
 * And in Investigations it's all over the place. Both  and for Kay Faraday
 * Rock Howard from Mark of the Wolves seems to suffer from this. He struggles with his "evil side" inherited from Geese Howard, despite being raised almost entirely by Terry.
 * The evil influence is not from his father
 * Very subtle in Fire Emblem: Radiant Dawn, but present nonetheless: One of the most amoral members of the Greil Mercenaries turned out to be  Possibly averted in that despite being amoral, he is also fiercely loyal (ahem) to Ike, and for lack of a conscience of his own, he often follows Ike's.
 * In Fire Emblem Blazing Sword we have minor villain Erik, son of the corrupt Marquess Darin. In the next game in the continuity Erik has grown up to be exact same tyrannical ruler his father was, and repeats his predecessors mistakes step by step even going so far as to kidnap a little girl(for different reasons but still). This is bothersome as Darin wasn't truly evil until he met Ephidel and Erik seemed repentant after being defeated by Eliwood and Hector.
 * It's regularly noted in Umineko no Naku Koro ni that Battler has more than a few similarities to his grandfather, Kinzo. Considering that Kinzo is certifiably batshit insane in every sense of the word, as well as the fact that crazy seems to run in the family in general, we can assume that this is not a good thing.
 * Gotha's family in Dragon Quest V starts from a masculine Pankraz, having a son who has as much masculinity as him when he grows up and pretty much suffers very similar fates as him when he's married. While this guy's not as strong as his father, he has an ability to use healing spells, which carries onto his son, who can even cast a better multi healing and revival spells while still being a hard hitter. Also in the game he wonders if he can catch and train monsters like his daddy does.
 * In Crusader Kings, characters will pass onto their offspring a tendency to have similar stats. This was strong enough in earlier versions that a form of Darwinian evolution could be observed, where since characters with higher stats were more likely to survive and to succeed as rulers and pass their traits on, everyone in the late game had insanely high stats
 * In the backstory of Nox, the world of Nox's Legendary Hero wipes out every member of the Exclusively Evil Necromancers, but spares the last Necromancer, a mere baby, sending her off to be raised by the primative but morally neutral Trolls without any knowledge of her true heritage. She, of course, grows up to be the game's Big Bad, and inherits not only her ancestors' total evil, but also their raging Goth-ness. (Although the Wizard ending implies she was possessed by the evil spirits of all her evil ancestors, and without being indwelt by them she's actually a pretty decent lady).
 * Likewise, in the Divine Divinity series, the Hero spares The Antichrist because he's just a little baby, and tries to raise him as his own son and a champion of truth and justice. This does not work out, at all (although the failure was at least in part caused by external factors, namely the Religion of Evil sending an agent to tempt him to the Dark Side).
 * From Yandere Simulator; Ayano's mother was herself a yandere. That is, in fact, how Ayano's parents met. (As in, her mother kidnapped her father and forced him to love her.) And supposedly her grandmother was just as bad. It's even hinted that her family line is not 100% human.

Web Comics
"Agatha: I believe another forty-five point three seconds, and i would have exploded or something. Agatha: Oh, yeah... I have got to try that again!
 * Ada Lovelace from The Thrilling Adventures of Lovelace and Babbage inherited a poetical disposition from her father, Lord Byron. Ada's mother taught her mathematics to hold back this pernicious influence.
 * In Misfile the main reason Cassiel is treated as being dangerous and untrustworthy is because her uncle is Lucifer. One wonders how much of her Jerkass nature is precisely because of this treatment, certainly both Vashiel and Rumisiel bring up her family tree at every opportunity.
 * Agatha of Girl Genius has seemingly inherited much of her father and uncle's heroism, despite having been raised in secret away from anything that would particularly require her to be heroic. Othar even lampshades this when he mentions that she ran straight at danger without thinking twice, despite her claims that she wants to stay normal and hidden. Their ancestors were Not So Different in that they were fearless and charismatic (even above the level of enhanced charisma common to Mad Scientists), but mostly using this to act as barbarian warlords (it's implied they could conquer a proper empire for themselves, but didn't bother to rule anything beyond small loyal area and only extracted tribute from others).
 * Various other characters speculate about which lot of relatives she's going to take after.
 * Sometimes she acts just as crazy, if generally in more benign ways:
 * ...or something. Under the circir/circumstances I/I am forced to admit that yo/you are most most likely oneoneone of the family...
 * yesss... most likely, in/in/indeed."

"Lord Womble: ...and the lack of screaming, ranting, and egregious violence has been noted."
 * On the upside, people don't worry about Agatha too long, unless they are more concerned with the Mongfish line -- the Heterodynes (with but one known exception) weren't sneaky. Queen Albia sees people's minds, and appears to be concerned only about "charismatic" part, as she welcomed Agatha, but saw fit to administer a little loyalty test to her courtiers.


 * Invoked, then subverted in Everyday Heroes by Jane Mighty; originally from a family of villains, she follows her best friend and joins an Anti-Villain team who find stolen items and steal them back for their rightful owners. She quit villainy after her friend is killed
 * Cited by name, then later Justified in Narbonic: Helen notes that she didn't always want to be a mad scientist, but then notes the trope name. Justified later in that.
 * Candi Levens' ancestry includes Honeybee Samuel and Dwayne Lloyd. Sure enough, she and her sisters are completely obsessed with sex. Especially bad for Candi, because she's a Doom Magnet who therefore Can't Have Sex Ever. At least, not with Muggles. She's initially in denial of this fact; it doesn't end well for.
 * This is the whole plot behind Sire. Each character is descended from a literary character. Anna and Susan are descended from  Emile is descended from   and more are soon to follow.
 * The sons of Luk River from Irregular Elis. They formed a Badass Family of Superheroes with a lot of hereditary powers.
 * In The Order of the Stick, Ian argues that Elan has to be like his tyrancial father. In fact, he takes after his Chaotic Good mother.
 * Elan inherited his mother's alignment and his father's love for the dramatic. Nale inherited his father's alignment and his mother's love for excessively complex plans.
 * In Thistil Mistil Kistil, Loki's reaction to Coal's Berserk Button is to observe that his father was The Berserker.
 * In Nip and Tuck, a paternally caused explosion inspires this observation.

Web Original

 * In the Whateley Universe Whateley Academy has an official 'club' known commonly as The Bad Seeds. Admission? One or both of your parents must be a supervillain. Some kids take to this like ducks to water, some resist, some don't know what the heck to do, some are pretty clueless even for teenagers. Nacht has a supervillain mother who is constantly trying to get Nacht to use her powers to help mommy commit crimes; Nacht doesn't mind the crime part, but she really doesn't want to spend time with her mother. Jobe is a ruthless, amoral genius bio-devisor who even looks like his supervillain dad; his dad hates that junior doesn't have a flair for mechanical devises instead. Carmilla has Deep Ones in her mother's ancestry, and is the grandchild of Cosmic Horror Shub-Niggurath on her father's side; she's taking the Screw Destiny approach right now. And so on...

Western Animation

 * Teen Titans: Robin actually told Raven he admired her Screw Destiny response to the prophecy she would help her demon father destroy the world.
 * G.I. Joe's Serpentor, made with the DNA of Julius Caesar, Napoleon Bonaparte, Attila the Hun, Philip II of Macedon, Alexander the Great, Ivan the Terrible, Vlad the Impaler, Hannibal, Genghis Khan, and Grigori Rasputin to be the world's most evil and effective military leader. So naturally, his plans fail.
 * They didn't manage to get Sun Tzu's DNA (who was targeted specifically to give Serpentor wisdom and prudence), so they replaced it with Sergeant Slaughter's, whose strategic abilities can be summed up as punching people in the face while insulting them. Hilarity (and failure) Ensues.
 * Zuko of Avatar: The Last Airbender is a painfully complicated (as usual) case—according to Iroh, his inner conflict and confusion in Season 3 is revealed to be due to What else would you expect from someone related to Mark Hamill?
 * However, this is averted with the rest of the family. Ozai and Iroh are Sibling Yin-Yang, as are Zuko and Azula. If, how do you explain Iroh being the nicest of the family?
 * Iroh's good side is suggested, by Fanon at least, to have something to do with his trip to the spirit realm after Lu-Ten's death.
 * Supported further by a flashback to Iroh writing a letter to Zuko and Azula, in which he gleefully jokes about burning Ba Sing Se to the ground. He even laughs heartily after he writes it down. Not exactly in line with the gentle wise old man who only kicks a ton of ass if he absolutely needs to.
 * The Lion King II: Simba's Pride used this with Nuka, the only son of Scar. He is evil, very ugly, and receives a Disney Villain Death. Ironic, as the film was supposed to be subverting In the Blood. The film was supposed to have Scar's son as a protagonist, but that wasn't possible because it would've made its Romeo and Juliet cousins.
 * In the Chip 'n Dale Rescue Rangers episode "Le Purrfect Crime", the heroes are menaced by Fat Cat's lookalike cousin Maltese de Sade. Learning that he's Fat Cat's cousin is all the information Monterey Jack needs to know the guy is rotten, an assumption that is quickly confirmed.

Real Life

 * Psychological research shows that a lot of our personality traits are partly inherited from our relatives. For example, a child born from parents with deficient levels of Monoamine oxidase A (a neurotransmitter that helps to control aggression and impulsiveness) is likely to be more aggressive than a child with normal levels of the "warrior gene". However environmental factors are just as likely to inhibit those chances they will be exhibited in behavior if the child was born in a supportive household rather than a abusive one, the latter which makes the likelihood of them exhibiting aggression 10 times more likely.
 * This is a common subject of debate concerning "dangerous" dog breeds such as pitbulls.
 * Whoever assassinated Emperor Caligula (likely his own Praetorian Guard) also murdered his wife and children, out of fear his insanity was hereditary. Seeing as his nephew Nero was just as bad, this may have had some truth to it.