Cats are not naturally social in the way dogs are, and multi-cat households can cause chronic stress, conflict, and health problems when feline territorial needs are not adequately managed.
Multi-cat household stress is one of the most underrecognised welfare problems in companion animal keeping. The social structure of cats — evolved for resource-based, low-density living — is poorly suited to being cohabited in small spaces with unrelated conspecifics. The stress is often expressed subtly: one cat monopolising resources, another hiding for most of the day, indoor toileting outside the tray, and chronic low-grade illness. Owners who interpret the absence of visible fighting as evidence of harmony may be missing chronic stress in their animals. Environmental management — adequate resources in separate locations, vertical space, predictable routine, and gradual introductions — significantly reduces multi-cat conflict, but the most welfare-positive approach is honest assessment of whether a given household and its residents are suited to the number of cats being kept.