The period where cats are most receptive to learning about the social environment (including other cats) is the socialisation period which occurs between approximately 2 and 8 weeks of age. Kittens who have friendly encounters with other cats during this time are more likely to perceive other cats positively.
After about two years of age, acceptance of another cat can be a bit random, but they will very rarely totally reject another cat in the long-term. After a time even those cats that do not become great friends can still learn to tolerate and live with each other by keeping to their own territory.
I hear people often say that they think it will be easier to start with one kitten and then, later on, adopt another. I can see the logic - getting two might seem like rushing into a bigger commitment but really, it's not much different. In fact - bringing in a second kitten later will likely be a much harder process.
If you have a young cat at home and want a second, consider adopting one kitten of the opposite sex, as same-sex cats are much more prone to fight each other for dominance. Your resident cat will still be young enough to recall having fun with her littermates, and the new kitten will be more than happy to oblige.
Cats are family-oriented and usually live with their relatives. Cats will sleep together, share common feeding areas, and groom one another within family groups. For this reason, cats often do well adopted in pairs.
Pairs are Happier
Despite their independent natures, cats are social creatures that need companionship to thrive. Left alone, a cat can develop behavioral problems, and in some cases, even show signs of depression. Cats in bonded pairs, on the other hand, are more likely to be better adjusted.
Male cats tend to be more social and affectionate with both humans and other cats. They commonly form strong bonds with other cats in the home, even when they are not from the same litter. Females, on the other hand, are often more standoffish. If you are looking for a cuddle bug, adopting a male may be your best bet.
A laid-back, older (neutered) male cat may enjoy "mothering" a kitten - male or female. They usually make better mothering substitutes than spayed females. Females, in general, are less accepting of newcomers.
You should expect the introduction process to take no less than a week but could take much longer depending on your cats' temperaments. Before bringing a new cat home, ensure that you have the time and resources to handle this process with care and compassion.
Understanding the Kitty 'Terrible Two's'
Between the age of 6 months and 2 years, your kitten will be reaching physical and sexual maturity. They will grow out of being a pure bundle of energy but, like human teenagers, they will be learning and exploring more of the world around them.
Follow this simple rule: one box per cat, plus one extra. So if you have two cats, you should have three boxes. Making sure everyone has their space can help ease elimination issues. Some owners prefer a hooded box, but some cats don't like them.
The great thing about two kittens is that two hardly costs more than just one! Kittens can share litter boxes, cat trees, food and water bowls, beds and toys! Some rescues will offer discounts on two kittens who are bonded or from the same litter to ensure that they go to the same home.
Single kitten syndrome is the idea that young kittens, when raised with other young kittens and cats and then adopted into a home by themselves, can become aggressive, anxious, stressed, and even develop behavioral issues like inappropriate chewing/scratching and inappropriately using the litterbox.
Despite the common belief that cats are solitary animals, they're actually incredibly social beings who thrive when they have feline friends from an early age. That's why I always recommend adopting two kittens, or adopting a solo kitten only if you already have another young cat in the home for the kitten to befriend.
So, can cats share a litter box? If you have multiple cats, they may be comfortable enough with each other to share the same litter box. However, there are several reasons, including territorial behavior, why some experts would advise at least one extra litter box in your home.
If you have an adult female cat and are looking to adopt another female, a kitten or a youngster is your safest bet. Two female kittens raised together should be fine as well.
If either party appears aggressive, fearful or just unsure, don't force the interaction. Separate them again and continue with scent swapping. Cat and/or kitten may vary with their reactions; from curious to unconcerned, playful to nervous. Make sure both have plenty of space and the ability to retreat if necessary.
"Most researchers agree that we can rate cats on a dimension called sociability, which encompasses traits that characterize cats as friendly and loving," Posluns says. "Based on the few studies of cat sociability, little research supports that male cats are more affectionate."
The differences between a male or female cat
Usually male cats are much more cuddly, especially after being spayed, while females are more aggressive or defensive by their maternal nature.
Look for a cat who doesn't mind sleeping on the couch. Cats who are very playful and confident when they see other cats are more likely to get a long with a kitten or an energetic young adult. The new cat will keep them occupied and will be young enough to adopt the rule structure of the older cat.
Don't worry too much about the gender of the cats involved. Age and temperament are the most important factors. Adult cats will usually accept a new kitten much more easily than they will accept a new adult cat. Cats are territorial, and your cat may resent an adult feline intruder.