Existing cats may often need an adjustment period when a new pet enters the household. Gradual introduction is often needed. This can be accomplished by shutting the new cat in a room with food, water, litter box, bed and toys for several days or longer. This gives the existing cat(s) time to become familiar with the new pet's odor and vocalizations. The older the established cat is, the longer an adjustment period may be needed. Some older cats never come to accept a new family member. After an adjustment period, the cats should be allowed to interact between a slightly opened door. A cage or screen door between cats can also be used for this introductory period. Do not force the cats to interact-- allow them to do it on their own. Some growling, hissing, swatting and hiding will be normal. Intervention may be needed if the cats truly attempt to injure each other. Most cats will eventually adjust to the new family member if given time and not crowded.

A veterinary examination is very highly recommended for all new pets, ideally before they enter the household. New pets should be evaluated for overall health, vaccine status and potential to carry disease or parasites to your existing feline friend(s).