as knowledgable in cartoons as I am, I've never heard of Little Alvin and the Minimunks.
That's probably because it's brand new. Check out
www.chipmunks.com
It's a new project out from Bagdasarian.
It sounds interesting. I haven't had a chance to see it yet myself.
And yes, I think Tiny Toon Adventures could count. It's not technically young versions of the Looney Tunes gang (we have Baby Looney Tunes for that!) but Buster is obviously a "Bugs" character, Plucky is a "Daffy" character, Hamton is a "Porky" character, Little Beeper is a "Road Runner" character, Calamity Coyote is a "Wile E. Coyote" character, Dizzy Devil is a "Tazmanian Devil" character, Furball is a "Sylvester" character, and Sweety is a "Tweety" character. Babs doesn't exactly have an adult counterpart, but there is the character of Lola Bunny and I would consider her Babs' adult counterpart. Lola didn't show up until "Space Jam" as far as I know, but she has definitely shown up as one of the main or at least supporting characters in the ongoing Looney Tunes comic book from DC. Shirley MacLoon isn't really based on a Looney Tunes character that I know of, but she is a parody of real life personality Shirley MacLaine (who started the New Age movement). Elmyra is another character that's pretty well original. I might almost say that Montana Max could be a young version of Elmer Fudd, since they're the two main villians for Bugs and Buster, but Montana could also be likened to Yosemite Sam. I don't know.
Hey, anyone know if there was ever a "young" version of Foghorn Leghorn? I can't remember any off hand.
This same kind of concept was used on the Saved By the Bell: The New Class show.
One other example of this is Disney's "Jungle Cubs" series. I used to watch it some and it's pretty good. It's the story of The Jungle Book when they were all young cubs, thus "Jungle Cubs". Of course, Mowgli hadn't come along yet, but Bagheera had his hands full keeping Baloo out of trouble. I'm pretty sure the baby elephant (the one who was a young kid in the movie) was there too, along with Kaa and Shere Khan. I'm thinking the monkeys and vultures might have been in there too. And King Louie was definitely there.
While I'm talking about The Jungle Book, I might as well mention Talespin. This is an awesome Disney cartoon that I well remember discovering by accident around 1990 or so. I mainly was interested because I saw Shere Khan, Baloo and Louie all there and all still called their same names. Although this Shere Khan, Baloo, and Louie wore clothes, they were very similar to their Jungle Book characters in personality traits. Anyway, it's a great cartoon, but not an example of a "Young" or "Baby" cartoon series. That's just an example of Disney reusing their hit characters. (But let's not start on Disney. I still love Disney cartoons and movies, but seriously, do we really need a Bambi II? Well, whether your answer is yes or not, Disney is making it. I've long since determined that Disney is determined to make a sequel to every animated movie they've ever made. Basically to squeeze every bit of money they can out of all their franchises. Most of the time the sequels really aren't needed and really aren't all that good. The only exception I've really noticed is Toy Story 2, which was awesome and quite possibly better than the first. That's a rare thing, there.)
Anyway, yes, I think Muppet Babies really did get a trend going. I think it worked out well for most shows and maybe not for some others. There were probably examples of this before Muppet Babies but I'm too tired to think of it right now.
Let's just be glad we didn't see this trend on some other great cartoons. I'm sure Baby G.I. Joe and Baby Transformers would have gone over real well.