Kid Characters in Cartoons: Yes or No?
Internet critics have panned episodes of their favorite shows that feature child characters who were meant to be relate-able to them but weren't. These are often the product of executive meddling, which usually has no idea what it's talking about. However, the concept as a whole shouldn't be thrown out entirely; if it's handled well, it can be saved by good writing. What bothers people most is a specific use of "The Scrappy" trope, not the existence of cartoon children in general.
Not all child characters are annoying; they can be, but at varying degrees. Age is relative to maturity in some shows instead of the other way around. For instance, a show that focuses on high school students will depict those younger than them as childish; the same goes for middle and even elementary school students. Each person is given a characterization or at least one trope, but some might not be as well-developed as others (or the writers weren't given any sort of direction because sometimes people just don't give a damn about what they're producing). This is a big problem when creating a well-rounded cast, but it isn't the main reason that people often complain about child characters who were supposedly added for their benefit.
The main problem concerning child characters is that they are not part of the original concept of a show or part of the principal cast. Cited examples include the Teenage Mutant Ninja Turtles and The Real Ghostbusters. The viewers at home are supposed to relate to these characters and live vicariously through them according to the networks, but that rarely ever works. The critics do not want to be compared to these characters because they don't do anything interesting or of worth to the main plot. The fault here lies in these characters taking attention away from the series' protagonists or doing their jobs for them due to circumstances, which is usually something stupid. The mistake made in these situations is the overuse of this trope combined with overall shoddy writing. Rein in these types of episodes and spruce them up a bit more, and then you may have something worth the air time.
One example of a show that gets this right is (big sarcastic surprise) My Little Pony: Friendship Is Magic. While the quality may have declined in recent seasons (causing people to argue among themselves and leave the fandom), earlier episodes handle the issue of child characters rather well. At first, I didn't like the episodes about Cutie Mark Crusaders; they aren't poorly-written characters or anything, but they aren't aimed at my age demographic either (assuming the show as a whole was aimed at a general audience, which it pretty much is). For those who are in their target audience, they are probably not a problem (at least, not as much of a problem as in other cartoons of old). They even became tolerable to me after a while (though the abridged series' depictions of them helped too), that is until the writing took a bit of a downhill turn when it came to certain characters sending mixed messages and getting hit hard by the stupid stick. The point is that while the CMC are not the stars of the show, they are an important subset of characters that have every right to exist within the show's canon. Non-canon or fanon characters will remain in the hearts of the individual fans or fandom, so there's no need to manufacture them for the sole purpose of having characters who are meant to be stand-ins for the viewers.
In conclusion, kid-of-the-day plots are usually garbage writing if not done properly and sparingly. As the name implies, no one likes a Scrappy. If there was some greater meaning behind it, such as a contest winner or Make A Wish kid, that is more of a one-time gimmick or reward rather than a formula for success. The last thing a successful franchise needs is some kid character shoehorned in for the sole purpose of having a stand-in for the audience. That's what fan fiction is for, and it's never in short supply. The intended audience already has it covered, so stop thinking it's a necessity to keep kids' attention.