Yes, It Can Happen to Your Dogs, Too… The Cassandra Effect and Multi Dog Households

Prevention is sadly, hard to sell.

You might be following the story of a well known dog influencer and the tragedy she faced of losing three of her dogs in one incident. A quick summary of what occurred is that this person had 7 bull breeds living together. Lots of content online that I skimmed through made me uncomfortable in terms of proper multi dog household management (i.e. I saw a lot of red flags in their interactions, body language, and situational setups). This person boarded her dogs at a facility while she was on vacation. When three of the dogs were let out together, the youngest went in to attack one of the others, who then immediately had a heart attack and passed away. The third dog got in on it and the instigator severely damaged him, ultimately causing him to pass as well from his injuries. The instigator was observed to be staying in a heightened state of arousal and aggression post the incident and was then euthanized.

The sad part is, people tried to warn her of the risks involved with multi dog households, especially with her bull breeds and her same sex pairs. They tried to offer her advice. But she believed it would never happen to her. It’s incredibly difficult to SELL PREVENTION. I see it everyday in my line of work. No one wants to believe that it could happen to them. But yes, it can happen to your dogs too, if you are not careful - especially if you have large breeds, breeds predisposed to dog aggression, same sex pairs, and large groups living together. Housemates can absolutely fight even after living together “peacefully” for months to years.

I recently listened to the Modern Wisdom podcast titled “#1042 - Dr. Andrew Huberman - How to Reclaim Your Brain in 2026,” where the host, Chris Williamson interviews Andrew Huberman and they were discussing the “Cassandra Effect” which I had never heard of before. Google Overview defines it as: “a general metaphor for having valid warnings ignored… [meaning] when someone accurately foresees negative outcomes or speaks important truths, but their warnings are disbelieved or disregarded by others.” It was given this name from a story in Greek Mythology where a Trojan princess named Cassandra had the gift of prophecy, but then in turn was cursed so no one would believe her predictions. While I had never heard of this term before, it’s what I live with every day with dog owners, especially ones who have multiple dog households. It describes the frustrations of true professionals perfectly. No one wants to hear about prevention and what “could happen” from me (or any one else like me), because “nothing has happened yet.”

Everyone has the same story: there was never a problem until there was. EXCEPT… professionals like us who are well versed in these breeds and well versed in aggression can look at cases, situations, and scenarios and point out all the flaws and all the red flags of what went wrong prior to and leading up to the event. How?

Because first and foremost (speaking for myself) I’ve lived through it with my own dogs. At the time of writing this, I’ve personally owned 9 Rottweilers, 3 German Shepherds, 2 mixed breeds, and 1 Dogo Argentino cross, all who were going to be euthanized for aggression before I adopted them, most with bite histories, and almost all with some type of dog aggression. I have also fostered multiple additional Rottweilers, German Shepherds, and Bull breeds who were integrated amongst my dogs at the time. I’ve made the very mistakes within my pack that I teach people not to do today. I’ve dealt with multiple fights and dogs trying to kill each other. It’s not fun, and yet I too was one of those “it won’t happen to me” people until it did. And now I know better and see where I went wrong. In the early years of my career, I didn’t hear much about prevention when it came to multi dog households. That’s why it’s a passion of mine, now.

Second, being a dog behavior consultant that specializes in aggression, I have seen and worked with thousands of cases of dog to dog aggression. These cases have ranged from mild squabbles to many situations where dogs have actually killed their housemate and every variation in between. I see the same patterns, over and over and over again. The owners say the same things and make the same mistakes. This makes it very easy to predict when things are most likely to go south in the future and when there is higher risk present. But, I recommend to ALL owners of multiple dogs to participate in basic management and safety protocols regardless of potential risk because it’s just the right thing to do.

And third, having any type of knowledge with dog behavior, aggression, and genetics (especially when it comes to certain breeds) empowers you to make better choices. Because you know the why, the motivation, and the potential outcomes that can occur.

And yet, we still lay victim to the Cassandra Effect and people still don’t listen to us when we try to help people PREVENT future aggression between their dogs. We are dismissed, sometimes diminished, and ignored. The dog influencer in the recent news that I am alluding to, actually created a video online not long ago mocking the fact that people have tried to warn her about being able to maintain peace between same sex pairs of bull breeds. And within her video was the dog who eventually instigated an attack on the other who had the heart attack. The irony is not lost on me. This mocking of truth did not end well for her, or her dogs.

After talking with other professionals and with clients, I wanted to write about why this tragedy could have been prevented. And in the words of one of my colleagues, let this be “a learning experience by listening to what others have to say… It’s about educating to prevent something further from happening and from others experiencing the same thing [in the future.]” This, coming from a colleague who is also a client of mine and who once upon a time, also, didn’t want to listen to me! Until she ended up with a fight a few years ago that made her change her perspective. Thankfully, now, she manages her pack of bull breeds well including the same sex pair that fought, and there have been no issues since.

But people shouldn’t have to wait to experience a fight before believing. It might be too late by that point. And for that I will continue to always share, promoting PREVENTATIVE education.

The first foundational red flag that I believe was definitely (and unfortunately) present was a lack of proper structure in the dog’s daily life at home in regards to boundaries, rules, predictability, some limits in freedom, and the elimination of competition between the dogs. Do I know this for a fact? No. But I can tell you what I’ve seen in their content. It includes dogs piled on top of each other (which can be competition for space). It includes dogs all over elevated surfaces (which can indicate a lack of any boundary in the home). It includes dogs who are brand new, being used for content involving other dogs before having a chance to decompress (which can place new dogs at an unfair disadvantage to begin with, continuing to allow stress levels to climb rather than dissipate). It involves seeing videos of dogs who were being fed food in close proximity of each other, literally inches apart (which can be blatantly creating competition). She probably never worked on independence training to allow the dogs to get breaks from one another. And she probably never worked on crate/confinement training for the dogs to have their individual safe places to enjoy their resources in peace and also to practice some impulse control. I realize that I’m making assumptions here, but this is the common pattern I see with thousands upon thousands of dog owners. All of these points slowly build tension and animosity over time. It can be very subtle, but that doesn’t mean it doesn’t exist. It doesn’t mean that it’s not building up until one last thing pushes one of the dogs over threshold.

For the dog that was the instigator in this case, the boarding situation most definitely added to the tension and the stress and the negative associations that were already brewing potentially from their home life. So all it took was perhaps the other dog “looking at him the wrong way” or “acting weird” because he was about to go into cardiac arrest, and that was it. That could have been what crossed the line of what he could tolerate and was enough to cause the attack. When dogs have a high level of baseline stress to begin with, it doesn’t take much to push them over the edge.

The next foundational red flag that likely also contributed to this tragedy was a lack of proper outlets, exercise, and mental stimulation. The whole “dogs need jobs” idea is truer than most people realize. Most dogs, especially young dogs (like the instigator here) need to be doing something. They need to be worked. While physical exercise is not the end all (nothing is) if these dogs don’t get a proper, legal outlet for their energy, then they WILL have all that extra energy to put towards other things, and most often those are things that you don’t want these dogs to put any extra energy towards (such as, aggression). Mental stimulation is just as important, especially given that mental stimulation can tire dogs out even more than physical exercise can. Both the brain and the body need to be tired out.

The particular case we are discussing here, involves a video where the owner responds to questions about the instigating dog’s physical and mental exercise habits. In this video she states that the dogs were “outside all day long,” together. Unfortunately, that’s not enough for a young bull breed (or any other active dog). Dogs will mosey about in a back yard and then stop when they get a little tired or bored. This is very different from when we do activities with them and push them to be tired. It’s the same as the difference between a person working out on their own versus with a personal trainer. We will always be pushed harder by someone else. Without these outlets, frustration slowly builds and can become a ticking time bomb to manifest in a way that is undesired.

Next is the fact that the dogs were boarded in a place away from home where they had access to be together. Any type of boarding facility is going to cause some stress on the dog(s). There’s the change in daily routines, there’s the uprooting from their territory, there’s the social pressure of all the other dogs present (even if they are not interacting with the other dogs, they still know that they are there), there’s the barking, there’s the smells (I believe that at least one of the three dogs was still intact so who knows if there were also any lingering smells of intact females present) … so many variables that could set a dog off.

I always have a rule that if you have dogs with high risk of fights OR have had any fights previously, that they should be separated with pet sitters or separated at boarding facilities. These higher stress levels, changes in routines, and not enough outlets paired with people who do not know the dogs as well as their owner, makes a recipe for disaster. This includes letting dogs out in a yard together. If one of the dogs decides to display aggression, it’s most likely going to be towards whomever is closest in proximity to them - their housemates.

The fact that the first dog who was attacked passed away immediately from a heart attack, means there was the potential that a pre existing heart condition was present. Unfortunately many breeds and mixes of those breeds are predisposed to heart issues. And even more unfortunately, sometimes they can still go unnoticed even with standard veterinary exams.

Dogs can absolutely be instinctively motivated into aggression towards a known housemate when something is “off” with them medically. I have seen numerous cases of fighting between housemates where the older dog was getting attacked. Then, come to find out a few weeks or a few months down the road, the older dog had a serious medical issue arise. People humanize dogs way too much and never want to admit that their dogs might “pick off the weak.” They’re still animals. A simple moment of recognizing an opportunity, a moment of weakness, is all it takes in some circumstances.

The last red flag that I want to address is the fairy tale story everyone wants to believe: that the third dog “stepped in” to protect the first one from getting attacked. The reason that large groups of dogs can pose a greater risk to anyone else is because of social facilitation. Social facilitation is defined by Google as, “the phenomenon where one dog’s behavior increases the probability, intensity, or frequency of the same behavior in another dog.” Social facilitation is always a concern. If one dog in the group starts to bark, they will most likely all start to bark. If one dog starts to chase a cat, the rest of the dogs will most likely start chasing as well. And if one dog starts attacking someone (dog, animal, or human) then the other dogs will most likely start attacking, too.

It’s simple - “there’s a fight, let me get in on it, too.” Especially when that’s what the dog’s genetics are screaming for… When this dog owner says that the third dog “stepped in” what they were seeing on the video was probably a hover and a freeze… which also could have been seen as competition or a threat from the instigator, because that’s what it is. If the dog who was attacked first didn’t pass away so quickly, then I have no doubt in my mind that the third dog would have ultimately been fighting with BOTH the other two, despite the fact that they were deemed “best friends.” Because that’s what happens in dog fights.

It’s easy for people to overlook these subtleties because again, no one wants to believe “it could happen to them.” I really wish more people would be open to getting advice from professionals on preventing tragedies like this. Just because we as professionals try to help people prevent what we KNOW is possible because we’ve seen it thousands of times, because we are being right early on, we get dismissed. I have had so many clients who didn’t want to listen because there had been “no issue yet.” And then a little while later, what I predicted came to fruition. Sometimes it was a wake up call and they could get their act together. Other times, it was already too late. As Chris Williamson said in his podcast, “Being right isn’t enough and being early can feel like you’re wrong.“

I’m not here to bash this particular owner or this particular case. My goal here is to spread awareness on the preventative measures that so many average dog owners pass up. There’s literally no down side to putting in the extra work and safety precautions to focus on prevention. If you want to know what you can do to prevent fights to the best of your ability, reach out to a professional who specializes in this, and stay tuned for the next blog post on it.

Don’t let it happen to you. Don’t be the cause of the Cassandra Effect.