A lot of people apparently liked cats in the '80s and '90s. And since the Broadway musical "Cats" was big in the start of the '80s (around 1982 I believe), perhaps that was the starting point for the feline theme of the next two decades- lol.
But anyway- yes, I also grew up watching Heathcliff and the Catillac Cats and I love it.
And speaking of all these cat shows, of course you can't forget "Garfield and Friends", which was another favorite for me. But I've never been the kind to try to choose between two- both Heathcliff and Garfield are cool to me. 
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