The Challenge of May-December (Cat) Relationships

One of the two most common reasons cat guardians come to me for behavior consultation is conflict between cats in the home (the other reason is litter box avoidance). A situation where cat-cat conflict can develop is when a new, young cat comes into a home with a resident, older cat. These “May-December” (younger-older) relationships can be rocky for many reasons, but there are things guardians can do to help.  

Note: For the purpose of this article, I will use “older cat” to describe an adult or senior resident cat and “younger cat” to refer to a kitten or young adult who is new to the home. The information below would also apply to homes where an older cat is new to a home with an existing younger cat. 

Why It’s Hard

There are different reasons it can be difficult to help a younger cat and older cat live peacefully together.

Energy Differences

Typically, though not always, a kitten or younger cat is going to be more playful and energetic than an older cat. This can lead to unwanted play attempts, disrupted naps, and general annoyance. An older cat may start to fight back and escalate what the younger cat intended as play into a fight. Or the older cat may start to avoid, hide, or run away. This can add to the game for the young cat, making things worse even if there aren’t direct conflicts or fights.

Orange tabby cat hiding face in paws
Why did you bring home the little monster?
Photo Credit: Alexas_Fotos/

Health Challenges

While cats of any age can suffer from medical concerns, older cats are more likely than younger ones. A cat that is in pain or uncomfortable due to a health issue may be less open to interacting with a new cat or playing. They could also be more irritable and less tolerant of the younger cat’s behavior in general. 

As a reminder, cats are very good at hiding illness or pain. Their behavior is often the first sign of an issue. Just because your cat doesn’t seem sick doesn’t mean they aren’t coping with something. 

Routine and Territory Changes

Cats, generally speaking, love routine and predictability. Adding a new cat to the home is going to change their life and that can be stressful. They may lose access to parts of the house where the new cat is settling in. Rest and relaxation could be affected by a new, active housemate. Plus, they now have to share you. Even if you work hard to give attention to all of your cats, it won’t be the same as it was before.

There are also new smells and changes to the older cat’s territory (your home). This can be unsettling for many cats but especially those who are more cautious by nature. 

Previous Experiences

When bringing home a new cat or kitten, ask yourself how long it has been since your older cat met an unfamiliar cat. They may have lived with another cat previously but if they met that cat when they themselves were a kitten, this is going to be a very different experience. Like most species, humans included, making new friends is easier when cats are young. Adult or senior cats who have never met another cat as an adult may lack the social skills to easily do so. This can lead to fear or aggression toward the new cat.

If your resident cat does have experience with meeting new cats as an adult but those experiences were negative ones, this will also increase the challenge of forming a new relationship.

How to Help

As you identify the challenges related to integrating your older and younger cats, there are many things you can do to help them feel safe and comfortable together. This is in addition to doing a slow introduction and having patience. Many cat-cat introductions can take months or longer. 

Medical Check

It is important to ensure both cats are healthy. Schedule a vet check for the older cat, in particular, to ensure they are not suffering from any hidden pain or discomfort. This graphic shows some ways pain can change how your cat moves that you may not have thought to share when you talk to your vet

Depending on your situation, your vet might also recommend medication to support behavioral health during the introduction. 

Home Setup

How your home is set up can make it easier for multiple cats to share. Have plenty of resources, such as litter boxes, food and water stations, napping spots, and scratching posts, and separate them so that the cats can all get what they need without having to get close together or taking turns. Use vertical space to create “high roads” and “low roads” so cats can pass through a space in different ways and avoid each other. Make sure there’s an escape route from perches and hiding places so one cat can’t trap the other. 

If one cat needs more breaks from the other, consider creating a “safe zone” that only that cat can enter. This can be done using microchip or magnet-activated cat doors placed into interior doors. 

Daily Routine

All cats can benefit from a daily routine that provides outlets for natural cat behavior, engages senses, and uses their mind and body. Kittens and young cats, in particular, need ways to burn energy, play, and explore. Interactive play, food puzzles, and other enrichment are all part of a daily routine that supports peaceful multi-cat households. 

Professional Support

You may need help implementing these recommendations or more to support your cats living peacefully together. If you need guidance on the next steps for your household and how to create a safe, happy home, reach out to a behavior professional.

A Happy Household

Even if they don’t become best friends, many cats with age differences can learn to share space and live in harmony. Be willing to rethink success however, your unique home may also see a happy outcome by creating separate spaces for the cats to enjoy life apart. Finally, remember that not all cats are meant to live together and the best thing for everyone could be not living together. Your goal should be to have two happy cats, whatever that looks like for them.

If you need help with and introduction or with conflict between your cats, consider scheduling a private behavior consultation.