I'd just not worry about it, TBH. My DS was also very easily scared by movies, and (at 7) still doesn't ever choose to watch them. He seems to be able to play playground games based on their characters nevertheless, and it doesn't seem to have been a problem! (Similarly, he's introduced playground games based on characters in books he's read and the other kids seem to have no trouble with them.) I think it's a lot too young to worry about cultural references. I let DS know from time to time that such-and-such exists and that I'm happy to take him to see it if he wants, and don't worry about it further.

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