Putting cats together to “sort it out” can establish fear and conflict. Give the newcomer a separate room with food, water, litter tray, hiding, scratching and height. Let both cats recover and investigate scent before they meet.
Scent before sight
Exchange bedding and let each cat explore the other's area separately. Pair the other cat's scent with food or play at a comfortable distance. Move to brief visual contact through a secure barrier only when both animals can disengage and behave normally.
Prevent competition
Provide several separated litter trays, feeding stations, resting places and escape routes. Increase contact gradually and step back after staring, blocking or chasing. Peaceful coexistence is a valid goal; not every adult cat wants a close feline friend.
