On page 184 of Murder at the Gardner, a Fat Cat employee in the art department explains from where the inspiration of Fat Cat came.
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"It was a committee. They took the big, heavy lidded eyes from Garfield"-

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"and the teeth from Heathcliff"

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"and the grin from the Chesire Cat"

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"and the wisecracks from Morris"

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"and the white gloves from Donald Duck"

"and they colored it purple to look different from the others, and behold!"

A piece of corporate art is born.