The Junior Counterpart is a character that serves as a younger Mirror Character to an older character. A character of this sort is often present to have similar origins, appearance, or personality to the older character, but is either more idealistic, naive, or reckless than the older character and always less experienced. It's far more likely that the junior is the protagonist as he is most often shown to be the underdog, with the senior functioning as a Decoy Protagonist.
The junior is most often presented as being a student or younger relative of the senior, but not always. Sometimes, the junior becomes the sidekick of the senior, other times it may be showing how History Repeats.
If a work follows the junior's Character Development, he most likely develops the same characterization as the senior if he doesn't already have it from the beginning.
Often generates a "You remind me of me" statement and might even carry a Weapon Jr.. If the junior is a descendant of the senior, overlaps with Generation Xerox. Compare Spin-Off Babies and Legacy Character.
- Asta in Black Clover is this to Yami, with both being social outcasts who have had to attain merit through hard work, very muscular, and wielding swords to fight. The difference being that Asta is cheerful and energetic while Yami is short-tempered and rude. Despite this, Yami acts as a mentor for Asta, teaching him how to sense ki as well as providing him with advice and reassurance, with Asta highly respecting him as his captain.
- Lyrical Nanoha: Nanoha is this to Gil Graham. Both of them came from and island nation on Earth (Gil from England and Nanoha from Japan), were introduced to magic after finding an injured mage in the woods, and eventually moved off world to join the TSAB.
- Usopp in One Piece is the son of Yasopp, a crewmember of a famous pirate crew, the Red Hair Pirates. Both of them are avid sharpshooters, with Usopp using a slingshot in similar effectiveness to his father's gun. Luffy recruits him for that reason.
- Shounen Hollywood - HOLLY STAGE has Daiki Tomii, the second "Tommy" of the eponymous group. Like Minoru, the first one, he shares his orphanage background, media interests, marketing color, and even his role as The Heart. The Hollywood Tokyo president chose him for Shounen Hollywood exactly because of those similarities.
- Many of the Robins are this in some capacity to Batman, but Dick Grayson is perhaps the closest to Bruce in origin, as his own parents were murdered and Dick was motivated to get revenge on the ones responsible. Unlike most sidekicks of his era or the rest of the Bat Family, he doesn't have a bat or darkness motif at all since he was designed to be Plucky Comic Relief. Later the third Robin, Tim Drake would grow to be the most like Bruce in personality and the way he approaches tactics.
- Cassandra Cain from Batgirl (2000) is this as well. Her origins are being a play on the idea of a single murder scarring a child so much they become determined to never let it happen again. She is canonically a better fighter than Bruce, incredibly stealthy, a living lie detector and very terrifying. But she lacks many of his other skills, is very reckless and impulsive, and her drive to save lives is so high she had thrown fights out of fear of killing her opponent or is known for Taking the Bullet.
- Roy Harper, back when he was Green Arrow's sidekick Speedy, was a young version of Ollie, not only due to his archery abilities, but also because he turned out to be as much of a ladies' man as his mentor.
- Shazam!: Captain Marvel, Jr. was one of, if not the first. Superboy, Kid Flash, Wonder Girl and the rest were all created to cash in on his popularity.
- Spider-Man has a few.
- Alpha is Peter Parker post-Spider bite but pre-Uncle Ben's death, right down to getting his powers while on a field trip. He's full of himself, irresponsible, and obsessed with fame. Making him not just a Junior Counter Part, but a foil in that he's what Peter would have been if he had never decided to try and grow up some.
- Spidey's daughter and Distaff Counterpart Spider-Girl counts. Like her dad she's bright in science, a chronic Determinator...and really unlucky when comes to love.
- Superboy is this to Superman in continuities where he's not literally a younger version of Supes. Typically like his mentor he's a young person trying to help people (but without the cape). Supergirl also counts in continuities where she's physically younger than her cousin.
- X23 is this to Wolverine. As his Opposite-Sex Clone she has the same powers, but even more of a problem controlling her Berserker Rage do to being raised as weapon since birth. Over time, she eventually learns to control her anger much better than Logan ever did.
- Once she takes on the mantle of Wolverine, she eventually gets her own in the form of her younger clone, Gabby.
- Invoked in Young Avengers wherein the team intentionally patterns themselves of their role models, The Avengers, in hopes of becoming Promoted Fanboys. Some members of the team are even blood related to their counterparts, such as Scott Lang's daughter Cassie and Scarlet Witch's kids Billy and Tommy (Billy got her witch powers whereas Tommy got Quicksilver's Super Speed).
- Young Justice's core four and founding members are junior counterparts to four of the founding members of the Justice League of America with Superboy (Kon-el), Robin (Tim), Wonder Girl(Cassie) and Impulse (Bart).
- Abraxas (Hrodvitnon): In this Godzilla MonsterVerse fanfiction, Manda has shades of this comparative to San. Both of them are and have always been insatiably curious which made them difficult for their elder caregivers to keep track of, but Manda's innocence is intact comparative to how San has billions of years of abuse, tragedy and darkness behind him.
- Black Crayons series: Annabelle Lennox to Sam Witwicky, they were both regular people who became aware of the Cybertonians because of their respective families: Archibald Witwicky discovered Megatron when he was frozen in ice and had the location of the Allspark imprinted on his glasses; William Lennox was attacked by a number of Decepticons and works with the Autobots in NEST. Sam and Annabelle have also befriended one Autobot in particular, Bumblebee and Ironhide, respectively.
- In Blue Moon, although Bella and Buffy don't meet until near the end, a few characters seem to consider Bella basically a younger version of Buffy given her relationship to Edward mirroring Buffy's relationship with Angel, save for the fact that this one has a chance as Bella can become a vampire to be with Edward without losing her soul. When Faith joins the Slayer army sent to Forks, she calls Bella 'Little B' as a further reflection of this, and the Slayers as a whole trust Bella to wield the Scythe in the fight with the Volturi.
- In Beneath the Planet of the Apes, the character Brent is a smaller, younger version of Taylor from the first film.
- In Carlito's Way, the main character is frequently told by others that young gangster Benny Blanco who comes to Carlito's club is a younger version of Carlito. Reformed Criminal Carlito, who thinks Benny is a cheap punk, doesn't take kindly to the comparison.
Sasso: What happened to you? What are you acting like this for? It doesn't make sense you should hate this guy, because this guy is you 20 years ago!
Carlito: [Angrily staring a hole through Benny across the room] Never me. Never me!
- Godzilla Junior (and Minya) count towards the trope, being younger and more naive (or, in Junior's case, tolerant of mankind) than Godzilla himself is.
- Marvel Cinematic Universe:
- As an adoptive son, Loki is in many aspects a younger male version of Frigga. She taught him magic, and he also "inherited" Shared Family Quirks (fidgeting with hands when nervous), her talent for deception, her elegant comportment and her fighting style (i.e. relying on speed and agility). Both are very perceptive about other people (lampshaded by Frigga in regards to Loki), not to mention that Loki is In Touch with His Feminine Side and beautiful in a feminine manner. Loki initially tried to rein in Thor's violent, impulsive side, and Frigga does the same with Odin. They even die similarly by attempting to protect another person and ambush a much stronger foe with a short sword/dagger and being Defiant to the End.
- Thor is very similar to his father Odin. Frigga's death in Dark World reveals how Odin is capable of the same Hot-Blooded, reckless and impulsive tendencies as his son. It gets taken up further in Ragnarok where Odin's brutal history of galactic conquest with Hela is revealed, making younger Odin seem much more like Thor was in the first movie. Thor in turn winds up losing an eye so that he physically resembles his father, while losing some of his Glory Seeker tendencies due to weariness over the people he's lost to be more like Odin in his later years.
- Peter Parker is a younger version of Tony Stark. The latter acts as his mentor and parental figure.
- X-Men: Apocalypse: In certain respects, Jean Grey is a younger female version of her father figure Charles. She's a Nice Girl with a Friendless Background who is tormented by her telepathy because she has difficulty blocking out the thoughts of others, and she suffers from Past Experience Nightmares, which makes the two of them Birds of a Feather. Jean becomes a source of emotional support to Scott after his brother dies, which mirrors how Xavier comforts her when she's distressed. Jean is compassionate towards a dehumanized Wolverine even after she had witnessed him butcher all of Stryker's soldiers, just as Charles is forgiving of Magneto's mass murder because he can still sense the goodness in his old friend. Jean adopts the Pstandard Psychic Pstance that her mentor no longer uses, which reinforces the idea that she's a surrogate variant of Daddy's Girl.note Their sameness is also displayed visually because Jean wears a 3/4-sleeve blazer which is similar to the Professor's (albeit in a different colour), and conveniently, they're both beautiful in a feminine way (Xavier is a Long-Haired Pretty Boy).
- Harry Potter: It gets noted several times that Hermione has quite a lot in common with the Hogwarts professor McGonagall. Both of them are intelligent, logical and book-smart women, and both of them even at times have a comparable "steely glint in [their] eye".
- Crops up a several times in A Song of Ice and Fire, oftentimes by blood relation.
- In A Game of Thrones, Ned notes that his daughter Arya is pretty much his late sister Lyanna reborn; sharing her personality, appearance, and interests.
- In A Storm of Swords, Jaime Lannister notes that Loras Tyrell is pretty much himself as a youth: a gifted, reckless, impulsive knight who is very close to his lookalike sister and obsessed with fame.
- Margaery Tyrell is presented a younger Cersei Lannister, both being daughters of a great noble house having, both having great ambitions, both marrying kings, and having a great dependence on an older relative (Cersei's father Tywin; Margaery's grandmother Olenna).
- Renly Baratheon is presented as this to his older brother King Robert. Not only does Renly have nearly the same appearance as Robert did in his youth, but Renly has a charismatic, gregarious personality, something which Robert lost in the years since his rebellion.
- At several times in the story, Littlefinger compares Sansa to her mother Catelyn Stark, claiming that Sansa is starting to resemble her physically.
- S Club Juniors were this to S Club 7, before growing up to be S Club 8.
- Nowi from Fire Emblem Awakening is a younger counterpart of Tiki from Fire Emblem: Shadow Dragon & the Blade of Light, since both of them are young-looking dragon girls who use Dragon Stones to morph into massive dragons. And considering that a now Older and Wiser Tiki can be recruited in Awakening....
- The Legend of Zelda:
- In The Legend of Zelda: Twilight Princess, Zant is one to Ganondorf. Zant envied the prosperity of the Light World much like Ganondorf did with Hyrule. This desire eventually got corrupted into a desire for power for its own sake, and Zant eventually acquires a source of power to gain what he desires. However, Zant is a Psychopathic Manchild and Entitled Bastard who throws a tantrum when things don't go his way, while Ganondorf remains composed to the end.
- In The Legend of Zelda: Breath of the Wild, Riju and Yunobo are younger counterparts to the Champions Urbosa and Daruk respectively. The former are much less confidant in themselves compared to the latter but still perform heroic deeds with Link's help.
- Axl of Mega Man X7 is one for X - in fact he replaces X for a while until all the 8 Mavericks of the game are defeated. He plays similarly to X, but without access to charged attacks that X is popular for. Axl undergoes Divergent Character Evolution in the next game, though.
- Super Mario Bros. has Bowser Junior, Bowser's son, and Donkey Kong Junior, the son of the first Donkey Kong who would grow up to be the Donkey Kong we know today. The series also ran with the concept after Baby Mario appeared in Mario Tennis. Since then they've introduced Baby versions of Luigi, Peach, Daisy, and Rosalina existing simultaneously with their adult counterparts. The latter two haven't even appeared in any official non-spinoff titles yet.
- The Super Smash Bros. series has Young Link and Toon Link, who are younger, faster versions of the full-grown Link. Melee also has Pichu, a younger relative of Pikachu who is weaker and downright reckless.
- How to Hero features Hatboy who is this to Hatman.
- Scootaloo of the Cutie Mark Crusaders from My Little Pony: Friendship Is Magic is a younger Rainbow Dash, sharing the same athletic tomboy personality and love of speed. Scootaloo eventually becomes Rainbow Dash's surrogate little sister/protege.
- The Legend of Tarzan has Jabari, the baby elephant, as a younger counterpart for Tantor. Jabari not only looks identical to Tantor as a child, but has the same cowardly personality.
- At the end of ReBoot's third season, after Mainframe gets backed up and restored in the midst of a system crash, Enzo's icon is left in Game Sprite mode, and is therefore recognized as a foreign entity instead of inhabitant, leaving his leftover data from when he lived there as a child to get copied into what becomes known as Little Enzo. Given how much darker his personality had become, "Big" Enzo doesn't like the kid at all for reminding him of how he used to be.
- The main and recurring characters of Tiny Toon Adventures are teenage (barring certain characters like Sweetie and Sneezer) counterparts of the characters from the classic Looney Tunes cartoons, often even sharing the Looney Tunes characters' personality traits. While still considered the junior counterpart of Elmer Fudd, Elmyra's personality contrasts that of her mentor, in the sense that she means no true harm to animals she sees, yet is considered a dangerous threat to them.
- From Xiaolin Chronicles, there is Ping Pong who is basically a younger smaller version of Omi with green glasses and a french accent.
- Virtually everyone on the Team in Young Justice is a sidekick, relative, clone, or Legacy Character to an older superhero. Even Static, who had no prior relationship to any heroes before he got his powers, quickly attaches himself to Black Lightning.