For decades, influenza A virus research focused on birds, pigs, and people. Since the early 2000s, cats and dogs have quietly entered the conversation. Canine influenza viruses established themselves as stable lineages, and highly pathogenic avian influenza viruses have been increasingly detected in cats. For veterinary professionals, this shift matters. Companion animals sit squarely at the human animal interface, sharing homes, airspace, and sometimes food with people. That proximity creates opportunities for viral adaptation that were not seriously considered a generation ago.