Cartoons have a tendency to get spun off into new shows with younger versions of the original characters. No one is quite sure why producers do this, aside from the opportunity to make a new franchise for a new demographic out of an older, successful property. Often the concept of the original show is dropped entirely and replaced, but sometimes it's adapted to an elementary- or middle-school setting. Frequently parodied, due to the absurdity of some of the examples.
Note that those are usually notprequels, and not part of the original show's continuity. It's usual for people who supposedly met for the first time in the original show to meet in the "younger" show, or for characters with notably different ages in the original show to be babies/middle-schoolers at the same time. If they are descendants, then it's Spin-Offspring.
Related to Recycled IN SPACE! and High School AU.
Contrast Time Skip, which tends to make the characters older instead. Compare Young Future Famous People, which does this with real people.
Anime and Manga
In America, Toonami aired the 1989 Dragon Ball Z five years before the original 1986 Dragon Ball, making it come off as this to some viewers who didn't know the original order. The first thirteen episodes of Dragon Ball had aired in syndication in 1995, but didn't do well.
The whole manga get a colored Super-Deformed spin-off, called Dragon Ball SD.
Panyo Panyo Di Gi Charat features an even younger Digiko and Puchiko having adventures on Planet Di Gi Charat. It's not immediately clear if it's actually a prequel, or an alternate continuity. As usual, if a prequel, it messes with the previously-established continuity a bit — they're still known as Digiko and Puchiko, even though these are supposedly just aliases they go by on Earth, and Piyoko appears, even though no-one seemed to have any idea who she was when she "later" appeared in one of the specials for the original series. Also, Dejiko is more optimistic and cheery instead of being a lazy Jerkass, and Piyoko is pure evil instead of just wanting to kidnap Dejiko for ransom. Given how silly Di Gi Charat is, this isn't as big a deal as it could be, though.
He and Kotarou (also aged up to late teens) are listed as classmates, so it's likely some sort of work study program. Most of his class still have (age-appropriate for their new age) crushes on him, and as of the fifth chapter, no character who was an adult in the original (including Evangeline) has been seen at all.
The Tokyo Mew Mew manga contained Omake depicting all the characters in a fantasy kindergarten.
Attack on Titan has the Middle School AU spin-off manga Attack! Titan Junior High. It is pure, unfiltered crack involving the main cast going to school with the Titans, and deals with it as a Slice of Life comedy. It gleefully parodies the primary canon, as well as including numerous Shout Outs to popular memes and aspects of the fandom. Eren still hates the Titans, but the trauma of his mother being Eaten Alive is replaced with his cheeseburger lunch being stolen on the first day of school.
Possibly the earliest comic book example is Superboy, the young persona of Superman, whose adventures were published as early as the 1940s. This was adapted into Smallville, among other things.
Archie Comics actually did this YEARS earlier than Muppet Babies (in the 1960s, to be exact) with "Little Archie", taking place in the gang's Elementary School years, but it didn't have many copycats. "The New Archies" (both a cartoon series and a comic, both short-lived) came in the 1980s, and was based around their pre-teen Middle School years. The former appears to actually be in continuity (told nowadays as flashbacks), but the latter, with several replacement characters (Eugene for Dilton, among others), is mostly forgotten.
One final attempt (so far) of reviving "Little Archie" was New Little Archies in the early nineties, when the concept was redesigned.
And when the Archie characters became superheroes in the so-bad-it's-not-too-bad "Pureheart the Powerful" storylines, their younger selves became superheroes, too.
In July 2013 Archie Comics announced yet another effort at this, with a cartoon series called It's Archie, once again setting the gang in middle school.
Still Archie Comics, but not Archie-centered: Sonic the Hedgehog had two specials devoted to the concept of "Sonic Kids". These were stories of the Freedom Fighters as kids, before they went around smashing Robotnik's robots.
Pre-dating Tiny Titans is Teeny Titans, an in-universe parody from the early 1990s involving babified versions of Nightwing, Starfire, Pantha, Changeling, and Baby Wildebeest (turned into a magic transforming doll) and their battles against evil Mr. (Slade "Deathstroke") Wilson. The fictional "Teeny Titans" came about when the New Titans were strapped for cash and decided to whore themselves out via merchandising deals and was largely played for shock value as far as the team being horrified at how their cartoon show was a slapstick kiddie show.
Zbeng!, an Israeli comic about a group of teenagers (featured in a teen magazine), had a children spin off called "Zbengale" (which featured in a children's magazine).
Le Petit Spirou is a spin-off of Franco-Belgian comic Spirou and Fantasio, starring a younger, and markedly more impertinent and irreverent version of the main character. Some of the one page gags are flashbacks to the protagonist years as a toddler (rather than an elementary school kid) which centers mostly on the many hazards awaiting the dangly bits of a small child running half naked around the house. Has a bad, bad case of Comic Book Time, the first albums were set in the 60s/70s with a grandfather who'd been in WWI, nowadays the gags are modern (and the grandfather still the same age).
The French Comic BookSillage (Wake) has a spin-off series called Nävis, which is about the title character's childhood on a jungle planet and is written and drawn in a more humorous style than the parent series.
In the late 1970s, DC Comics introduced the "Super Juniors," baby versions of the Justice League of America. While these characters only appeared in comics once (a digest-sized one-shot), they appeared on a considerable number of licensed products (toys, linens, nursery furnishings, etc.) in the early 1980s.
Ultimate X-Men re-envisioned the team as teenagers, including members who were adults when they joined in the proper canon. The one exception is Wolverine, who, like his X-Men: Evolution counterpart, is still 150 years old, which made his affair with 16-year-old Jean a tad bit creepy. It's worth remembering that the original X-Menwere teenagers, so with the Ultimate Universe being a Continuity Reboot, having the team start at that age while shuffling the original lineup makes sense.
The Doctor Who Adventures kids' magazine has a strip called "Alien Babies" with main characters Blun the Slitheen, Simon the Cyberman, Strup the Sontaran, Eldast the Silurian and Chas and Chelsea the Weeping Angels. Other babies come and go, often a baby version of the monster in the previous week's episode (taken to a ridiculous extreme in the issue following "The Rings of Akhaten", which featured a character actually called "Baby Grandfather").
Disney has been publishing a line of pre-teen-orientated Pirates of the Caribbean novels about Jack's teenage years since 2006.
Young Sherlock Holmes was a pastiche of Sherlock Holmes supposedly telling the early life of Holmes and Watson when they first met as teens. And apparently before Holmes figured out how to solve crimes by logical deduction.
The Danish (original) movie series Olsen-banden (Olsen gang) and the Norwegian Olsenbanden and Swedish Jönssonligan (The Jonsson gang) remakes had spin-off movies with the titular gang as kids.
Which was set in The Fifties even though the characters were middle aged during original films - which were released and took place in The Seventies and The Eighties. It might just work for Benny, who was quite younger than Egon and Kjeld (in the Danish version at least), but that just screws up the premise further.
A variation is Disney's successful line of preteen-oriented novels about the adventures of the teenage Captain Jack Sparrow.
Sweet Valley High has spun-off two "kiddie" versions of the characters: Sweet Valley Twins (set when the characters were in middle school) and Sweet Valley Kids (when they were in elementary school). The former was well received and heavily promoted via a retcon character Amy, who was Elizabeth Wakefield's best friend in the "Twins" book but her mortal enemy in the main "Sweet Valley High" book and ultimate led to a villain-based spin-off series based off of the "Unicorn Club". The later was reviled by fans as being soulless tie-in. Reversed with Sweet Valley University, which put the twins in college.
Meta FicFan Fiction example: Look Who's Talking, the Doctor Who day care center outside continuity, with toddler versions of every Doctor Who character, from the This Time Round setting. Best known for the Story Time series, casting the adult Who characters in fairy tales for the kids...
In possibly the most bizarre example, long-running British sitcom Last of the Summer Wine spawned a spin-off called First Of The Summer Wine, featuring the main cast as teenagers in the 1930s. This included both (at the time) Suspiciously Similar Substitutes for the third man of the Comic Trio, despite the fact that, in Last, Compo barely remembered one of them was at the same school, and the other one was clearly established as a newcomer to the village. Since this is a show about drunk and arguably senile elderly Brits, you could chalk it up to Unreliable Narrator.
Sesame Beginnings, a direct-to-DVD Edutainment Show for kids younger than the Sesame Street demographic (ie the under-2s), starring Baby Big Bird, Baby Cookie Monster, Baby Elmo and Baby Prairie Dawn.
Ant And Dec's Saturday Night Takeaway had a segment featuring "Little Ant And Dec". Thankfully not an Unusual Euphemism, this featured a pair of kids who slightly resembled Big Ant And Dec interviewing somebody in a faintly rude fashion.
The short-lived Young Hercules, directed at teen and younger viewers, featured the semi-sterilized adventures of an adolescentishHercules through ancient high school.
Psych got two of these. There was a set of short cartoons between the shows where it showed Shawn and Gus as children. Then at the next season, Shawn and Gus appears in shorts clips as teenagers during the mid 90's during the commercials.
Like many other tropes, this one was parodied on Muppets Tonight, when a tape of Seinfeld and a tape of Muppet Babies (yes, in-universe) got tangled together, resulting in the sketch "Seinfeld Babies".
'Newborns' is a popular way for characters in a line of toys to get even smaller and cuter, e.g. Pound Puppies and Puppy In My Pocket.
Teenie Beanies, which were available at McDonald's for several years, were this to Beanie Babies. Some Teenie Beanies were even given diminutive names of their larger counterparts; e.g., the Teenie version of Ants the Anteater was called "Antsy."
My Little Pony's "So Soft" line, which oddly styles the baby ponies more after human infants instead of equine ones. This is even the case in the toys based on Friendship is Magic, which explicitly shows ponies, babies or otherwise, to be quadrupedal.
In one of the most bizarre examples (which in hindsight, was also tactless and kinda stupid) the already-young Cabbage Patch Kids had a line of Cabbage Patch Preemies, even smaller versions of the dolls. In a move that everybody except the Cabbage Patch People saw coming, making a cute little doll out of frail and weak premature babies infuriated a lot of people. Discussed in number 2 of this article.
Yoshi's Island features the Yoshi tribe trying to keep baby versions of the regular Mario characters safe from Kamek and Baby Bowser. Its sequel has the current-day Bowser and Kamek traveling to the past in a search for MacGuffin Babies, terrorizing the Yoshis and babies (including himself) of that time period in the process. No, the plot doesn't make any sense.
Incidentally, Yoshi's Story was all about Baby Yoshis saving the day for the grown-ups.
Spin off baby versions of Mario, Luigi, Peach, Daisy and Rosalina have appeared in the Mario Kart series. Baby versions of Wario, Donkey Kong and Bowser have appeared in other titles.
Pokémon often introduces pre-evolved forms of certain Mons in each new expansion of the Pokedex. Who gets a baby form seems to be dependent on the character in question. Some get them based on their popularity, and others received them because they appear too "big" or "advanced" to hatch out of an egg as is.
In Hyperdimension Neptunia Victory, IF and Compa, two of the playable characters in the previous two games now appear as babies due to Neptune traveling back in time.
Square Enix did this with a couple of Final Fantasy characters in the Kingdom Hearts series. Most of these characters were originally in their late teens or early 20s in their respective Final Fantasy games, but their Kingdom Heartscounterparts are in their early to mid teens. This includes Zack from Final Fantasy VIInote Actually, Zack makes his first appearance in Kingdom Hearts: Birth by Sleep, which takes place 10 years before the original game. So, he's likely in his 20s in the present, just like his Final Fantasy counterpart., Selphie, Seifer, Fuu (Fujin), and Rai (Raijin) from Final Fantasy VIII, and lastly, Tidus and Wakka from Final Fantasy X. Squall Leonheart is an exception, as he is instead aged up to his twenties.
For the record, Baby Looney Tunes started off as a line of merchandise, further exemplifying the need to wring every dollar out.
There are at least two shorts where the Elmer/Bugs rivalry started as kids. One of them is part of a movie, in which Bugs thinks they must have been the youngest... and then sees a baby Coyote in diapers chasing a Road Runner egg with legs.
Done in 1944 in Bob Clampett's "The Old Gray Hare" and in 1980 in Chuck Jones' "Portrait Of The Artist As A Young Bunny". And arguably even earlier in 1943 in Clampett's "A Corny Concerto" - depends on whether the Ugly Duckling character is a representation of Daffy as a baby or not (and that's up to you).
One other short starred a baby Wile E. Coyote and baby Road Runner called "Little Go Beep", though unlike Baby Looney Tunes's show, it was more in the spirit of the actual cartoons from the Golden Age.
Done straight when All Grown Up itself got spun-off as Angelica and Suzie's Pre-Skool Daze.
For those of you who missed it, the Rugrats was already about babies, it got a spin-off in the form of All Grown Up and then that got its OWN spin-off, completing the vicious cycle of over-milking a once good idea.
When the producers of Batman: The Animated Series were told to do a "teenage Batman" show, at first they seriously thought about quitting but instead they came up with Batman Beyond (a sequel series featuring Bruce Wayne's successor).
Bruce Timm has stated that before doing Batman Beyond, the network had initially wanted them to do a series focusing on Batman mentoring teen versions of the Justice League. Thankfully, Young Justice was nowhere near as bad as we feared.
The Sponge Bob Square Pants episode "Goo Goo Gas" provides a variation: Plankton invents a gaseous substance that turns anyone who comes in contact with it into a baby. Naturally, this results in Mr. Krabs, SpongeBob, Squidward, and the rest reduced to adorable babies for most of the episode.
The Disney Hercules cartoon, who was technically that age during the movie, but not for most of it (it happens in-between Hercules being accepted as Phil's apprentice and the completion of his hero training).
X-Men: Evolution, in which most of the featured characters are re-imagined as teenagers attendinghigh school. This wouldn't completely count considering that many of the characters in the show were teenagers when first introduced in the comics (especially the original five), and some of the older characters (Professor X, Wolverine, Storm, Magneto, etc.) retained their canon ages.
Sabrina: The Animated Series featured the adventures of Sabrina the Teenage Witch at about age twelve, with Melissa Joan Hart's little sister as the title voice. Harvey was a skateboard nut (that could explain a few things, actually), and replaced the live action show's Alpha Bitch with a new alpha bitch named Jem Stone, who was the old antagonist, but twelve and vaguely gothy. The theme song is eager to point out that Sabrina's "the greatest" and has "super magic", but, since she's the protagonist of a show directed at preteens, she's predictably sort of a loser.
As with many examples of this trope, the series also ignored the original canon. In the pilot special, Sabrina didn't even know she was a witch until she was sixteen.
Well, the actual original canon, the Sabrina the Teenage Witch comic book, shows that Sabrina had her powers and was a witch since at least grade school (per several "Little Archie" stories).
Disney's Jungle Cubs which was a spin off of The Jungle Book featuring the animal characters as preteens and Kaa and Shere Khan as their allies.
They tried taking this tangent with Strawberry Shortcake a few times, most notably in with the 2003 series by way of the launch of the Strawberry Shortcake Baby line, featuring baby Strawberry Shortcake, kitten Custard, a younger puppy Pupcake and an unnamed teddy bear being prominently displayed on products meant for infants and toddlers. The show tried going down the path with just one episode hand waved to be Apple Dumplin's dream, but featured baby Ginger Snap, baby Orange Blossom and baby Angel Cake. The baby books added baby Blueberry Muffin. A baby Huckleberry Pie was designed, but very infrequently used.
The Mojo/Longshot arc of the X-Men comics, which featured the mad ruler of a world based around film and television creating the "X-Babies".
The X-Babies were largely based on (and identically drawn as) a brief appearance of the actual X-Men reverted to childhood forms in the original introduction of Longshot to the team (Annual #10). They did a decent (though not perfect) job of keeping the relative ages of each member scaled to the others. Created two annuals later, the "official" X-Babies (who are clones, not altered originals) were cheekily introduced with a "they're back" blurb on the cover.
Eventually, X-Baby villains were created, and an X-Baby version of Apocalypse destroyed the Mojoverse.
Gail Simone's Gen13 introduces The Authoriteens; Kid Apollo, Daybreaker, Nestling, the Contractor, the Intern, and Jack Hatfield (the Spirit of Small Towns). They turn out to hail from an entire universe of Spinoff Babies.
A Muppets Tonight sketch, where two tapes of old network shows got tangled together, resulting in the creation of "Seinfeld Babies".
An episode of Wonder Showzen features a sketch titled "Wonder Showzen Preemies" with the regular cast as babies in an obvious Muppet Babies spoof (Nanny even appears, shown from the socks up as a large pair of lips on legs — in keeping with the style of Wonder Showzen, the preemies actually have "two nannies"). At the end of the sketch, the children watch their own favorite show, "Wonder Showzen Embryos".
A TV Funhouse sketch, "Fetal Scooby-Doo", in which fake hauntings were exposed by a gang of prenatal detectives.
On Community, Abed imagines a baby spin-off of the study group, Greendale Babies.
Parodied by the web cartoonHomestar Runner, in the Strong Bad Email high school, where Strong Bad claims he, Homestar, Strong Mad, and Marzipan were "a team of super sleuths" in high school, then goes on to claim "In middle school, we were a bunch of melon-headed babies with giant eyes and enormous imaginations! ... And going even unnecessarily further back, we were all a bunch of plucky parameciums! ... Before that we were... Romans. In Roman times. And Don Knotts was always showing up."
Similarly, episode 7 of Teen Girl Squad (supposedly Strong Bad's independently-published comic book) was "Teeny Tiny Girl Squad".
In Yu-Gi-Oh! The Abridged Series, Kaiba has a flashback to his and Mokuba's childhood in the orphanage. Upon the cut-away from the present, you see the title Jim Henson's Kaiba Babies and hear littlekuriboh singing the Muppet Babies theme song.
The Guild posted a joke trailer for a spin off for "The Guild Babies". But because Bladezz is so much younger than the rest of the characters already, he is a fetus.
There is a parody nostalgia website for the nonexistent show The Adventures of Li'L Bill & Hill And Friends. What makes it actually funny is the executives' claim that any resemblance to a Presidential administration is entirely coincidental, although we the fandom are too smart to fall for that!
Comedy Central's series Lil Bush turns George W. Bush and other figures from American politics into grade-school kids, and in doing so it works according to exactly the same rules as other examples of Spinoff Babies.
In the spirit of the above, but played straight in Europe with of all people, Pope John Paul II and Padre Pio, in Piucci and Lolek. For no real reason they're still dressed the same but now in boyish form, offering spiritual help to troubled children.
The Powerpuff Girls spoofed this in the "City of Clipsville" episode by depicting a flashback where Professor Utonium accidentally turns the girls into babies, then he does it on the rest of Townsville. There's another flashback later on that spoofs the Time Skip variant, by having the girls speed up time and give up fighting crime to become air-headed teens, as have the Rowdyruff Boys.
Satirized in a South Park episode, a questionable incident that occurred in pre-school prompts the boys to flash back and look adorable◊.
One Robot Chicken sketch parodied this with Terminator. "Come with me, the Terminator Baby, if you want to live!" At the end, Sarah Connor comments about how Skynet must be running out of ideas for terminators.
Robot Chicken also did Lil' Hitler which was semi-accuratenote Germany occupied Czechoslovakia then Poland before war was declared by Britain and her allies, well from the US perspective.
Lampshaded in one episode of the Garfield and Friends animated series. Jon was looking into marketing Garfield for TV. Using Applied Phlebotinum and a Magical Computer, the network executive Jon was talking to showed off various ideas of TV shows he has to Jon, among them a baby Garfield complete with Lorenzo Music making cute cooing sounds. The executive also mentions that it was the latest craze.
There was also the Stand by Me parody where the Spooner Street neighbors are childhood friends.
In Sheep in the Big City they ran a fake commercial for Secret Military Organization Babies wherein General Specific, Private Public, and the Angry Scientist were babies.
Sort of parodied in the Justice League Unlimited episode "Kids' Stuff". Four of the main heroes get turned into 8 years olds and act like smaller versions of themselves mixed with typical little kid archetypes. It's a funny episode for a lot of reasons.