The OP's comment just now is on the right track:
certainly could be just a small cat.
would be more common in science, but for a different reason than you guessed: is actually the correct character for a child animal, but it's not one of the 1945 -- er, 2136 as of last year, is it? -- . Since looks and means almost the same, it took on the added responsibility of being the simplified form of .
I think for the anthropomorphism case those characters would need to be switched. =p
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