From using a different art style to Snoopy acting more like a dog, Charlie Brown and his friends were quite different in the early Peanuts comics.
Charlie Brown, Peanuts Wiki
Snoopy - Wikipedia
comic strips
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Peanuts by Charles Schulz for January 15, 1978, GoComics.com
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Peanuts by Charles Schulz for June 15, 2003, GoComics.com
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