Yeah, foxes fall into the family group of Canids. In fact, cats and dogs (and foxes by extension) are so far apart that they aren't even in the same sub order. The lowest branch of similarity they share is the order grouping of Carnivora, which is sub ordered into Feliformia (Cats) and Carniformia (of which Dogs, Bears and other carnivores with long snouts but no retractable claws fall into).
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