Kids generally don't understand the concept that fictional characters are "owned" by companies, at least not right away. It takes a while before they're ready to understand that concept and how it works. When you're four or five years old, Superman is Superman and Mickey Mouse is Mickey Mouse, and you don't really think of such characters in terms of "properties" that companies own and make money from.
That's certainly how I saw fictional characters when I was a kid in the late 1970s. On animated kid shows such as FRED & BARNEY MEET THE THING, it didn't seem strange or notable at all to me that Fred Flintstone and Barney Rubble were on the same show as Ben Grimm/the Thing from the Fantastic Four. Why couldn't/wouldn't they be? After all, Marvel Comics was also running a GODZILLA comic wherein Japan's movie monster interacted with Marvel's superheroes, and my Shogun Warriors toys based on Japanese anime shows were also concurrently appearing in their own Marvel book. I figured it was just a matter of time before Captain Marvel (Shazam) tangled with the Incredible Hulk on TV, or that Luke Skywalker from STAR WARS would meet Apollo from BATTLESTAR GALACTICA. Why wouldn't they? If it seemed like a cool idea in my child's mind, the adults that made these shows, comics, and movies would realize it and make it happen sooner or later (hopefully sooner).
I think I got my first clue that things didn't work that way when I was ten years old in 1982 and saw an ad in a Marvel book for the second Superman/Spider-Man crossover (the one wherein they teamed up against Dr. Doom and the Parasite). I noticed that the ad said DC AND MARVEL COMICS PRESENT. I had known for some time that some of the comics I read were labeled "Marvel Comics" and others were labeled "DC Comics," but I never really thought about what that meant in terms of characters meeting or teaming up. I figured that even though they were different companies, they both made comic books so their characters could meet up any time and it was no big deal. I had no inkling of all the business and legal matters involved in making that happen, or how indeed Godzilla managed to appear in a Marvel comic book. By the time I was twelve, I finally figured it out and understood why VOLTRON couldn't cross over with ROBOTECH (though that DID eventually happen in comic books published decades later): they were products of different companies, and many, many things needed to happen legally and financially for that to be possible, even if many people thought the idea was cool.
So...how old were you when you first began realizing that fictional characters were corporate-owned entities governed by different financial and legal considerations in their depiction, especially if they belong to different companies?
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