Setting Cats Up for Success Includes ‘Gaslighting’ Them
Imagine you are an introvert, meeting someone for the first time, and they hand you your favorite candy bar. They’re wearing your favorite band’s T-shirt and they smell like your favorite cologne.
Dr. M. Leanne Lilly calls for similar groundwork when introducing cats in a “demilitarized zone”—a place of peace and safety where cats can smell and hear each other, with positive reinforcements to set them up for success.
“Because I can make the other cat smell like you without you touching the cat. So we get the cat’s nose to lie to them: You snuggled that cat earlier; you just don’t remember it,” said Dr. Lilly, a clinical associate professor and section head of behavioral medicine at The Ohio State University College of Veterinary Medicine.
“I’m gaslighting cats for a living,” she joked, drawing laughter from the audience during her session, “Fighting Felines—Managing Inter-Cat Aggression Problems,” Friday at AVMA Convention 2025, which took place in conjunction with the 40th World Veterinary Association Congress in Washington, D.C.
Affective Aggression Types
Addressing affective aggression between cats starts with understanding it, Dr. Lilly said. She defined affective aggression as “distance-increasing behavior backed by the threat of harm” and covered different motivations and management approaches for aggression by type:
Effectively managing affective aggression, also known as reactive aggression, depends on understanding the context, body language, and environmental factors that may trigger the behavior, she said.
For example, with play-related aggression, providing a safe, alternative target like motorized toys can help redirect unwanted attention. Dr. Lilly also advised ending play sessions with something the cats can swallow, because play is “abbreviated predatory behavior.”
“Imagine if all your play was hanging out in your fake kitchen, and you never got to pretend to eat those cookies you pretend baked, but you also never got to eat real cookies—that could be kind of frustrating,” she said. “So we want to make sure we’re not increasing stress by increasing frustration.”
One idea would be to put a bell on the aggressor cat, so the “stalked” cat can identify where they are.
“Don’t put bells on your target kitties,” she added, getting a few chuckles. “That tells the aggressor where to find their prey or inappropriate play target, and that’s not helpful.”
Dr. Lilly encouraged avoiding reprimands or punitive disciplinary measures, as that may promote fear and aggression both toward the owner and potentially between the cats.
With pain-related aggression, identifying and treating the source of pain is necessary and may fully resolve the issues. Similarly, redirected aggression would require identifying and addressing the original target.
In other circumstances, while hissing is often associated with fear-related aggression, yowling is a classic sign of territorial aggression, directed at “noncommunal cats at the edge of their territory,” Dr. Lilly said. The point to remember here is that it is the cat that decides who is in their community.
“It doesn’t matter how many cats are in the home, the cat decides if you are a household cat—just like you can have people who live in your apartment building, but they are not your family,” she said.
Once the type of aggression is identified, treatment and management can be tailored to become more effective.
If a stray or a squirrel outside the window is causing territorial or redirected aggression, applying a window film as a visual block may be a simple solution. To help alleviate social stress, providing sufficient space and resources is recommended to enable safe-access spots and allow for better “timesharing.”
Dr. Lilly shared clients’ stories, as well as some videos of behavior-modification exercises.
Because the first interaction between cats is predictive of their outcome, Dr. Lilly advises starting with scent exchanges. The goal is enthusiastic participation and positive emotional response, she said, so look for that “question-mark tail” or a curious chirp.
One way to easily transfer scents between cats is to use a washcloth. But if they are grooming off the other cat’s scent right away, it may be an indication to slow down.
When reinforcing with high value treats during these exchanges, Dr. Lilly suggested giving enough treats so the cats do not have to compete and providing choice, so they can enjoy treats next to each other or farther apart if they choose.
It is preferable to keep these exercises shorter in duration with more frequency, rather than one long interaction.
Another key behavior modification is teaching cats to move away from each other to interrupt before any aggression can occur. She calls it “going to your corners,” like in boxing rings, because that has a more positive and fun connotation than “timeouts.”
“If the client is only feeling frustrated, we’re not going to get good adherence,” Dr. Lilly said. “So, I actually try to make sure that we’re doing things that are slightly fun for the client, while I’m trying to convince the cats that they are also fun for each other.”
While not all interactions may rise to the level of aggression, tension may still exist.
Intercat tension occurs in 62% to 88% of households with two or more cats, said Dr. Ilona Rodan with Cat Behavior Solutions in Wisconsin, who presents on “Intercat Tensions: Recognition, Prevention and Management” Sunday at the convention.
