Really Was Born Yesterday

"She has a newness. Everything is for the first time... If I had learned she had been born this very morning, I would only be surprised that she was so old."

— Prince Lír, The Last Unicorn^note This is said the first time he sees the unicorn, who was indeed changed into a human woman only the previous night.

Subverting the old joke, this character really was born yesterday, or this week at least, either artificially aged or just plain made the age they are now. They tend not to understand slang, or much of anything else, and will misunderstand social rules with usually comic results. May also be the result of a person being born normally but kept in some kind of stasis and never being conscious during their development since they still awake as a 'new' person.

Behavior from such as the Manchild is to be expected. From the other end, they can exist on a strange perpendicular line with the previous trope and Wise Beyond Their Years.

Contrast Really 700 Years Old, compare Emergent Human, Become a Real Boy. They're often prone to Blunt Metaphors Trauma and Baffled by Own Biology as well. Can be coupled with Artificial Human if they were recently created. The extreme end of Younger Than They Look. Pairs well with Born as an Adult.

Note: Please be careful when adding robot examples as, broadly, they almost all count. As a general rule examples should be kept to those that act in a way that is very strongly reminiscent of the Trope description. Real Life examples may be added but should be related to medical conditions.

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Examples:

Anime and Manga

• Chii in Chobits. Not in a physical sense, her body is a robot that has existed for a while. But she's dead at the beginning of the series, and in the first episode she gets reincarnated into her own body. Her new self is very much born yesterday, having to learn everything.
• Yuki of Haruhi Suzumiya appears to be a high-schooler but is really a three-year-old alien interface thingy. Asakura is similar. They fit the trope even more closely later in the series, when Kyon and Mikuru meet them three years in the past and they still appear to be high-school age. And since the event that was the reason Yuki and Asakura were created (something about data created by Haruhi and the potential for evolution) happened on Tanabata three years ago, and Kyon and Mikuru went back to that same day, it's probable that they were only a few hours old or even less at that point.
• In Kemono Friends, the titular Friends are all Little Bit Beastly girls born from a live animal or biological samples of them coming into contact with Sandstar, and most of them are probably much younger than their appearances would suggest. The best example is definitely Kaban/Bag, the Token Human who is at most a few days old by the end of the series since she was born during the last Sandstar eruption after a bit of it came into contact with a human hair inside a lost hat.
• Yaoyorozu's second major work after Kemono Friends season 1, Kemurikusa, has something similar with the protagonist Wakaba. His childlike mannerisms and naivety are a problem in early episodes, but we later learn that it's really because he was born only a short time before meeting the girls. He's a partial reincarnation of the original Wakaba, who really was and acted like an adult.
• Combat Cyborgs Otto, Deed, and Sette from Magical Girl Lyrical Nanoha StrikerS, who, despite looking like teenagers, have barely a month of real memories (since they were artificially aged and imprinted mainly with combat skills).
• The title character of My Dear Marie literally tells the rest of the cast she was in fact born yesterday, much to the consternation of her creator who is barely trying to cover up the fact she's a robot copy of the girl he has a crush on at school (Mari). That she does in fact act like this doesn't help either. Luckily, the real Mari just assumes she means it was her birthday.
• Negima! Magister Negi Magi: It's noted at several points that despite being a middle-schooler, Chachamaru is technically only two years old.
• Neon Genesis Evangelion:
  • In the manga version, Kaworu is only nine days old when first introduced. As such it's really no surprise that he has No Social Skills and does things like accost Shinji in the shower while they're both naked.
  • Rei Ayanami also counts in certain versions. The "first" Rei who looks like a child in a flashback is hinted to be much younger than she appears, and thanks to the Body Backup Drive that is the "Reiquarium" she's effectively reborn whenever her soul is put into a new body. This effectively resets her personality but only to a point, as Gendo discovers to his dismay in End of Evangelion.
• UQ Holder!: Touta Konoe doesn't have any memories from before about four years ago, and believes he has amnesia. Turns out, nope, the reason he doesn't have memories going back further is that he didn't exist until four years ago.
• In Overlord (2012), all of the Nazarick denizens started out as simple video game NPC creations of Satoru's guild. Their existences as sentient living beings only started when they ended up in the New World alongside Satoru in his Momonga avatar. The contrast between their apparent ages and their actual ages is made clear in the Light Novel when it's noted that Sebas Tian, despite looking like an elderly gentleman and acting like one, is much younger than Climb. This also applies to the Goblins summoned by Enri using the Horns of the Goblin General. The Goblins look and act like seasoned veteran warriors, but they didn't exist prior to being summoned. The Horns actually created Goblins based on the "ideal" of what a Goblin is in the New World.

Comic Books

• Astro City: In "Shining Armor", Atomicus looks like a thirty-something adult male, but has the emotional maturity and understanding of a young child since he was created just a year ago.
• Tesla, the title character in The Clockwork Girl, is only a day or so old when Huxley first takes her out to see the natural world. She's delighted with all the things she's seeing for the very first time. He responds that he thinks he's never really seen them before now, either.
  • Huxley himself, despite the teenage-monster body, is only about a year or two old. It's also implied his dad is as protective and caring as The Clockwork Girl's is uncaring. Man didn't even name her and Huxley's dad is letting him ether his own mini-science project in the town fair, have a friend and defeats the boy.
• Victor from Runaways is a two-year-old cyborg who was built as a teenager and given fake memories to make him think he's a normal human teenager.
• Tailgate, in The Transformers: More than Meets the Eye ends up being this: when we meet him, he's been in a form of stasis for six million years, long enough to be a peer of Cyclonus, which should make him one of the oldest members of the cast. However, at one point, he reveals that he was created at Rivets Field. Cyclonus is surprised at this, pointing out that Rivets Field didn't fire up until shortly before the incident that placed him in stasis. Tailgate only confirms it: his body may have lasted eons, but his mind at the start of the series is only two weeks old.
• Rubble from Transformers (2019) was born at the beginning of the series. Unfortunately, his life is tragically cut short when he gets lost while trying to get home on his own and winds up stumbling across Quake by accident while the latter is murdering an alien.
• In Transmetropolitan, The Smiler's original pick for a vice presidential candidate was a two-year old first-term representative who had been cloned. He had a completely clean record, and no baggage from past scandals — that is, except the scandal of his actual identity.
• Madelyne Pryor, Scott Summer's first wife in X-Men was eventually retconned into a clone of Jean, but despite this she's pretty well socially adjusted until she goes nuts after Scott abandons her.
• Young Justice: Superboy. His exact age depends on the continuity, but he's generally freshly cloned.

Fanfiction

• The An Astral Drop in Heatherfield starts with Hope's literal moment of creation and ends only two months later - although she packs a lot into her first few weeks alive.
• No Plumbers Allowed: When Nobel blows up in the Hebert living room to demonstrate that he's immune to his own explosion, drawing attention, he tries to use this as an excuse. Danny just gives him a Death Glare and tells him to try again.

Film — Animation

• By the end of his film, the eponymous character of 9, a ragdoll, has only been conscious for (a very hectic) approximate one-and-a-half-days.
• Frosty the Snowman takes place entirely on the title character's first day of life.
• The Snowman is another classic Christmas special where a snowman comes to life, and throughout the film, the Snowman is no more than a few hours old. He ultimately lives for just one night.
• The Canadian animated short To Be involves a teleporter that works by duplicating the "passenger" and killing the original. The film is about the inventor getting called out on the immorality of this. After the protagonist is responsible for one iteration of the inventor getting killed, she atones for the crime by teleporting herself, reasoning that the guilty her has been executed, and the "new her" is innocent.
• Pinocchio: Due to being created suddenly on the night, and being thrown into the world alone the following day with almost no knowledge of how is the world surrounding him, Pinocchio becomes an easy target for awful people to tempt him into going with them for their own shady benefit.
• The Snow Queen (1957): Gerda tries to ask a baby goat where Kay is. The goat replies that it does not know anything because it was literally born yesterday.

Film — Live-Action

• Avengers: Age of Ultron:
  • Ultron himself serves as an example; though unlike the Vision, who's described as naïve, Ultron's lack of life experience, combined with a quick internet download, drives him insane and convinces him that humanity needs to be culled.
  • Invoked when Ultron accuses the Vision of naïveté.
    The Vision: Well, I was born yesterday.
• Rocky from The Rocky Horror Picture Show: "I'm just seven hours old..."
• The Wizard of Oz: As in the original book, the Scarecrow was only sewn together two days before he meets Dorothy.

Literature

• Ed'Bocaj from Almost Night appeared as a child when she was but hours old, and reached full adulthood in days, and was born with the mind of an adult, though she acted childish for fun.
• Beesong Chronicles: While the apis remember their lives as giant bees, they were non-sapient, so after their evolution they act very much like children. Cora grudgingly admits she can't blame them for killing her, since she had invaded their hive.
• F. Scott Fitzgerald's ''The Curious Case of Benjamin Button", and the film of the same title
• Dune: Thallo, from Paul of Dune is only nine, but appears seventeen or eighteen years old, his physical growth having been accelerated by his creators.
• Gaia, from the Gone series, was born four months after conception as a fully formed infant, and looked about sixteen years old after birth.
• Elva from Christopher Paolini's Inheritance Cycle aged physically to around five years old within a few days of her birth because Eragon, in his attempt to bless her newborn self, bungled a syllable and accidentally cursed her with the ability to "be a shield from harm" (instead of "being shielded from harm") . What's even creepier is that while she aged physically to around five in that time, she mentally developed the intelligence, reasoning capacity, and cynicism of a woman with several decades under her belt.
• The Last Unicorn: The page's quote at the top is about Lady Amalthea, who is immediately noticeable as having a "newness" to her—each movement she makes indicates that she's doing many things for the first time. This happens to be because up until that point, she was a unicorn.
• A Series of Unfortunate Events mentioned the idiom in one of the books, telling how you (the reader) were probably not born yesterday. The author adds, "Unless, of course, you were born yesterday, and in that case, welcome to the world, little baby, and congratulations on having learned how to read so early in life."
• The Scarecrow from The Wonderful Wizard of Oz was born two days before he met Dorothy for the first time.

Live-Action TV

• Dawn Summers in the fifth season of Buffy the Vampire Slayer is a weird case. History was basically rewritten so that Dawn and all related characters all remember her having been there since the beginning, so from their perspective, no, she wasn't born yesterday. However, she incarnated into human form at the start of the season and has no real experience being such.
• Doctor Who:
  • “Delta and the Bannermen” features the Chimeron Queen Delta and her unnamed daughter, who in the course of less than a day hatches out of an egg as a green, big-headed monstrosity and grows to the size and general appearance of a young human teenager. She doesn’t talk much, but she has a very useful scream.
  • "The Doctor's Daughter" has the title character, an Opposite-Sex Clone created when the Doctor was forced to stick his hand in a progenation machine at gunpoint. She only knows how to fight because that was all she was programed with, and only develops her own ideas as time goes on.
  • Luke and Sky Smith from the spinoff The Sarah Jane Adventures; Luke was genetically engineered into a teenage state, and Sky was introduced as a baby before rapidly growing to an appearance that resembled a twelve-year-old girl.
• Liam Kincaid, the protagonist of Earth: Final Conflict for seasons 2-3. Born with three parents (one of them an alien) he grows from infant to adult over less than one full episode.
• Kyle XY: The title character spent the first 17 years of his life gestating in an incubation chamber.
• The classic The Outer Limits (1963) episode "Demon with a Glass Hand" plays with this trope. Trent, the protagonist, begins the story by musing, "I was born ten days ago. A full grown man, born ten days ago." Actually, he's a robot from 1000 years in the future built to protect humanity from genocidal invaders.
• Stargate:
  • Adria, the humanoid Crystal Dragon Jesus of the Ori in Stargate SG-1, is carried for 9 months and born like any other baby, but she ages to young adulthood in about 24 hours.
  • The penultimate episode of the fourth season of Stargate Atlantis introduces the clone of Doctor Carson Beckett (killed by an explosive tumour in the latter half of the third season), who was unaware that he was a clone until the expedition rescued him from his creator and carried out DNA tests.
• Supernatural: Dean's daughter Emma, an Amazon, is conceived, born, and becomes a young adult within a couple of days.

Tabletop Games

• In Dungeons & Dragons, true dragons grow through distinct age categories, from wyrmling to great wyrm, growing larger and more powerful with the years. Time dragons, due to their unique connection to the timeline, have age categories of random durations, from hours to centuries. As such, a young time dragon the size of a fighter jet might have been born mere hours ago, while a time dragon wyrmling might be centuries old.
• In Nomine: This is a common occurrence, as an angel or demon who was first sent to Earth this morning will nonetheless usually be wearing a body that looks like an adult human. Although they aren't usually sent to Earth immediately after their creation, still there's a major learning curve for those new to Earth no matter how old they actually are, and it has much the same effect.
• This is very likely for a Promethean in Promethean: The Created. A Promethean is almost always created using an adult's body, but all they are "born" with is knowledge of a single language and basic motor skills - everything else has to be learned "on the job", so to speak. There is no cultural expectation for a Promethean's creator to teach it how to operate (technically, there's not even a Promethean culture to begin with), so that weird guy you seemingly can't help but dislike wandering down the street could easily be less than a week old.

Theatre

• Rocky in The Rocky Horror Show (and its film adaptation) is actually born onstage during the song "I Can Make You a Man". He's a real hunk of a man-baby, and (naturally) has the mind of a toddler, which makes it kind of concerning that his first sexual experience happens when he's less than a day old.
• In The Wiz, the Scarecrow's "I Am" Song is called "I Was Born on the Day Before Yesterday".

Video Games

• AITale:
  • Darius says he was just born, but he also says he’s 35 years old.
  • Likewise, Alaska claims he was born last night.
• All of the Murakumo Units in BlazBlue, to varying degrees.
  • Lambda-11 is of unknown age, but dormant until Kokonoe activated her during Continuum Shift. She awkwardly bonds with an insect in her story mode, but otherwise acts almost completely mechanical and obedient.
  • Mu-12 (Noel Vermillion) has been active only 5 years at the start of Calamity Trigger. It's unknown how much of this effect and her lack of memories contribute to her painfully shy personality, but she is still the most social of the Murakumo units.
  • Nu-13 is first activated during the events of Calamity Trigger, and can do little but destroy and yandere over Ragna.
• The Breath of Fire IV iteration of Ryu gives Nina a Naked First Impression in his first scene in the game; it takes a long time before the player finds out that he was literally summoned into being at that very spot six hundred years ago due to a botched ritual — the same ritual that summoned Fou-lu all those years ago split the functional god in half, and Ryu is the other half.
• In Devil May Cry 5, V introduces himself to Dante saying "I have no name. I am but two days old… Just kidding. You can call me V." Cultured Badass that he is, he's quoting from the William Blake poem Infant Joy. But he is only kidding about his name. At the time, he was literally two days old, as a Literal Split Personality.
• Genshin Impact deconstructs this trope in the backstory of Scaramouche. A puppet created by the Electro Archon, he was left to sleep in a distant mansion and eventually rescued by a samurai named Katsuragi. The people of Tatarasuna took in what appeared to be an amnesiac teenager, who at the time did not even know how to dress himself or brush his own hair. Under their care, he learned these basic skills as well as reading, writing, and the forging that was the town's specialty. But his inexperience with humanity and innocence made him ill-prepared to deal with manipulation or human mortality, eventually driving him insane with grief and rage. He became convinced that the world was filled with lies, starting down a path of revenge and villainy. All the while completely unaware that it had all been an experiment to corrupt the newborn puppet and make him into a useful tool.
• The Sylvari from Guild Wars: Eye of the North and Guild Wars 2 are this, as they are a new race just getting their foothold. You actually get to see the 'birth' of the first Sylvari in a cutscene in Eye of the North.
• Along the same lines as above, the Guilty Gear games have the Command Gear, Dizzy, who is technically only 3 years old, even though physically she looks like a young woman in her late teens or early twenties, due to the rapid development granted by her Gear cells. She's rather kind-hearted and gentle for a Gear, although this inevitably also comes with some social naivete.
• Kingdom Hearts:
  • In the game's first hours, Roxas is a "newborn" so to speak in Kingdom Hearts: 358/2 Days. He barely knows any words, doesn't know what friendship means and he is clueless about just everything. Later on, he develops more and grows a spine, gradually becoming the way he was in Kingdom Hearts II. it's justified because he is Sora's Nobody and born without any of his original self's memories.
  • Naminé, Kairi's Nobody, was created at around the same moment as Roxas, though we never see her as a "newborn" the same way. Her first appearance in Kingdom Hearts: Chain of Memories begins around around three and a half weeks after the event that created them.
• Grunt from Mass Effect 2 is a Designer Baby Super-Soldier and the only one of thousands that his krogan creator Okeer thought was worthy, and he's basically born in your cargo bay when you release him from his tank. He does come with some Neural Implanting, but you're the first person he actually talks to outside of Okeer talking to him while he was in his tank (when he was unable to respond). He was also deliberately designed to have his armored headplates not be fully fused together, unlike the adult krogan, which is reminiscent of how the pieces of a human newborn's skull aren't fully fused until some time after birth.
• Mileena in Mortal Kombat, didn't qualify for this Trope for most of the franchise, which claimed she grew up with her "sister" Kitana, and was thus several centuries old. However, in Mortal Kombat 9, the Retcon changes this so that Kitana meets her in the Flesh Pits right after she was "born", meaning Mileena is more-or-less an infant (although "born" fully grown) as far as her true age is concerned.
• Klaymen himself in The Neverhood. The world is a kind of Eden (both metaphorically and, er, metaphorically), so it's not surprising there would be some literally new people in it.
• The Nintendo Wars game Advance Wars: Days of Ruin gives us Isabelle, a very recently created clone who is believed to be suffering from amnesia when in reality she's never had any memories to begin with.
• In Overwatch, Orisa stands out as the exception to the robot rule mentioned about because her stated age is 1 month old, having been created by the (pre)teen genius Efi Oladele from the remains of an OR-15 robot that was destroyed in an attack by Doomfist. The developers specifically bring this up as something that makes her stand out from other heroes in the 'verse, some of whom have histories going back decades, and cited by Efi and herself as why she's still getting the hang of this whole "hero" business. For comparison the other Omnic who's a playable character, Zenyatta, is 20 years old and is portrayed as a wise mentor figure, even to characters who are older than he is.
• Paper Mario: The Origami King reveals that this is the case with Olly and Olivia. The Origami Craftsman who lives on Mushroom Island folded and gave life to Olly in preparation for the Origami Festival that opens the story of the game. When Olly rebelled and trapped the Craftsman, he subsequently created Olivia based on the Craftsman's plans. It certainly explains why Olivia seems so ignorant and naive about the world throughout the story.
• Rika from Phantasy Star IV is one year old, but looks just a little younger than Kyra, who is 18.
• Baton, the heroine of Tadpole Treble is literally born at the start of the game, thus making the first level a Justified Tutorial, as her parents teach her the way the world works. Her curiosity also gets her caught by Coda the pelican when she ignores her mother's warning, setting the stage for the rest of the game. Sonata, another tadpole met in Midnight Bayou, is described as also being born yesterday in the Bestiary, which makes his sophisticated serenade to Baton that much funnier.
• KOS-MOS from Xenosaga is activated for the first time during the events of the first game. Thus she is at her most robotic because she doesn't have personal data-experience. Although she does share data with a buggy prototype that was activated once before.

Web Animation

• The Most Epic Story Ever Told in All of Human History: Ridiculously Epic Fail is born during the events of “The Most Epic Supervillain Origin Story”. Due to being created from a mix of Ridiculously Epic and Epic Fail’s traits, he is born as an adult and already knowing how to speak.

Webcomics

• Aurora (2019): Kendal, the main character, came into being a few hours after the god Vash's soul was stolen from his body despite the body itself looking like a young adult.
• In Far Out, this is suggested to the main character as a possibility, instead of amnesia. Given he's a robot, it's a real one.
• In The Inexplicable Adventures of Bob! this is the reason the three peanut butter monsters—Molly, Golly, and Jolly—act so immature. They're only a matter of months old. The only reason they don't act like infants is that they're hyper-intelligent and learn quickly.

Web Original

• Mollymauk from Critical Role eventually confesses to the Mighty Nein that he woke up Buried Alive with total amnesia one day and considers whoever he was before to be a completely different person, meaning his current self is only two years old. Molly is on the more functional side of this trope, but the fact that he's new to everything means he's a massive hedonist with a fascination for new experiences, and strangely naive about a lot of aspects of the world.
  Molly: That's a thing? They have stores purely for candy? Will wonders never cease?
• Hanazuki, the title character of Hanazuki: Full of Treasures, was born in the first episode, and we're reminded of it in episode two when she tells Sleepy Unicorn she was born yesterday.
• Belphoebe in the Whateley Universe is a cloned drow created by one student (Belphegor) using the cloning chamber he'd stolen from another (Jobe Wilkins) and accidentally imprinted with a copy of his own memories. Hence while chronologically she's 0, she looks 16 and is considered that age by the administration, staff and students.

Western Animation

• Ben 10: Ultimate Alien: Eunice is a 16-year old girl who is found on a spaceship, and later in the episode is discovered to be a Unitrix splicing Gwen's DNA.
• In the Bluey episode "Born Yesterday", Bluey and Bingo hear the phrase "born yesterday" for the first time, which gives them the idea to have their dad join them in a game where they pretend he really was born yesterday. He acts fascinated by everything he sees and has to be taught different rules by Bluey and Bingo on what to do and what not to do, since he's supposed to be seeing everything for the first time.
• Cubert from Futurama was cloned from one of the Professor's more shapely back growths, and was 'born' as a young boy of around ten.
• In Get Ed, Ed was "electrogenetically engineered" and acts like he hasn't been around more than a few months. While he's already good friends with his teammates at the start of the show and knows about the basics of life like eating and bathing, he's still utterly amazed when he learns that "those signs with numbers on them" are the speed limit (you'd think a courier would know that) and generally tends to be naive.
• The copies of Pinkie Pie from the mirror pool in My Little Pony: Friendship Is Magic all have her same personality, but none of the knowledge, memories, or life lessons the original has learned throughout the course of her life. The result is a large number of obnoxiously destructive versions of Pinkie Pie (In other words, it's not pretty). One that got away pops up in the background of The Saddle Row Review implying that, if given enough time to live and learn on their own, they're fully capable of developing mentally into normal ponies.
• Peep in Peep and the Big Wide World is a baby male chicken about as intelligent as a human first grader. In one episode he recalls his entire life, which actually did start yesterday.
• In the Star Fairies TV special, True Love, Whisper, Jazz, Spice, and Nightsong were created in an instant, and are instructed as to who Sparkle is and who they are.
• Steven Universe:
  • Concept art for "Hit the Diamond" implies that one member of the Ruby Squad sent to Earth, the one with the gem in her leg, was literally created one day before their mission, which explains her Naïve Newcomer personality and general lack of self-confidence.
  • In "Know Your Fusion", Smoky Quartz points out that they don't know that much about themself yet as, between their debut episode and this one, they've literally existed for about ten minutes total.
• Young Justice (2010): Superboy. Not quite "yesterday", but he's 16 weeks old in the first episode.

Real Life

• In very rare cases, a person's brain can lose track of its entire memory making it seem like it has been "wiped", such as in this example. Victims generally retain a few links and don't lose everything, though it can happen. (There are also very rare conditions where every memory can vanish, just like that, and with no warning at all.)

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