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What To Do If My Older Dog Is Attacking A New Puppy

Bringing a new puppy home is exciting — but not for everyone in the family. Learn about what to do if your older dog is attacking your new puppy.

Bridget Reed

Updated December 01, 2022 • Published November 30, 2021

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What To Do If My Older Dog Is Attacking A New Puppy

Getting a new puppy is life-changing for all the members of your family and not just the human ones. If you already have a resident dog and are adding a new puppy into the mix, you should prepare for plenty of new routines, training, and beyond. 

While it would certainly be ideal for your younger dog to get along with your older dog, the reality is that sometimes, there’s some aggression connected to this transition to having another dog in the home.

If your older dog is attacking your new puppy, there are plenty of things that you can do to potentially alleviate the stress of the situation and ultimately smooth the transition. 

Continue reading to learn more about why your older dog might not take to a younger dog, how you can help your two pups get along, and how long you should wait for these two animals to get used to each other. Finally, read about what you should do if you’ve tried everything, but nothing seems to be a success. 

While so many great things come along with getting a new puppy, you have to keep in mind that your older dog will likely have mixed feelings for several reasons. You must respect this to help both of your pups get acclimated with each other. 

Why doesn’t my older dog like my new dog?

Once you brought your new puppy home and saw any sign of aggressive behavior from your older resident dog, you might be wondering: why does my older dog not like the presence of my new dog?

While it might initially seem baffling, there are actually several logical reasons why older dogs sometimes struggle when you throw a new puppy into the mix. Once you get to the potential cause of the problem, you could be one step closer to solving it and creating a harmonious relationship between the two animals.

It’s important to remember that just because your older dog is not yet fond of the new puppy does not mean that they are cruel or unkind. They need time to get used to the change, and there are some causes that could be exacerbating an already stressful situation.

They’re territorial

The first reason an older dog might attack or not be fond of a young puppy is that they are territorial of their space. Your resident dog views your home as their turf, and therefore, the new puppy poses a threat to that—a threat that your older dog is uncomfortable with. 

Despite being pack animals, dogs are highly territorial creatures. As a result, if your dog feels that their space is in jeopardy of being violated or overrun, they might panic and act out. 

If your dog has demonstrated any type of territorial behavior, such as standing duty by your windows, barking at your neighbors, etc.), you should thoroughly plan the dogs’ introduction before you bring your new puppy home. 

They miss being the center of attention

Think of it this way: for an older dog, a puppy is an unwelcome intruder. Perhaps they do not want to share their beloved family with an unknown intruder that they did not invite into their space. 

In the case that your older dog is used to having your complete, undivided attention, you will notice that they might become jealous. There are steps that owners can take to ensure that older dogs feel supported and appreciated during the new puppy transition. 

They’re being provoked

Puppies do not always have the knowledge to know that they are doing something that can be interpreted as rude or annoying to an older, more mature dog. Therefore, sometimes the older dog is not the perpetrator of the aggression at all: the young puppy is actually doing something wrong. 

It doesn’t matter how kind and friendly your older dog is; if the puppy is making them feel threatened or uncomfortable, they are most likely going to act out. Therefore, it’s important to deal with any aggressive behaviors that may arise. That being said, there’s no need to yell at or punish either of the dogs. 

How can I help my dogs get along?

Of course, it is perfectly possible for you to help your dogs cultivate a friendship or, at the very least, tolerance for each other. There are several steps that you will have to take to help your older dog and new puppy get along. 

Introduce them correctly

The first thing that you can do to help foster a bond (or tolerance) between your older and younger do is by taking the time to introduce them properly. First, be sure to choose a neutral territory. Ideally, this should be outdoors if weather and season permit. 

The two dogs should be walked separately on a leash, and the walker of each dog should come to the meeting equipped with “high value” treats that the dog will respond to. To begin, the dogs should be walked at a distance. They can see each other but should not be provoked by the presence of each other. 

If there are no signs of aggression or negative behaviors, each walker can give their dog a treat for a good job: they saw each other and didn’t show any negative behavior. You can repeat this several times. 

If the dogs appear to be relaxed and calm, you can reduce the distance between them when you walk them. When the dogs look at each other in a relaxed manner, you can provide each a treat.

Take the interaction slow, and have patience. Let the dogs tell you how far they want the introduction to go; perhaps they want to play, or perhaps they’re content just sniffing each other on their walks. 

Next, walk one dog behind the other, and then switch it around. If the dogs still seem to be comfortable, you can walk them side-by-side. Finally, you can allow them to interact with each other but supervise them closely. If either appears to be anxious, slow the introduction. 

The introduction continues when you get home. Separate the dogs with a high baby gate in your home. Keep an eye out for how they behave with each other through this fence, and if they do anything positive, you can offer them a treat. 

Watch their body language

Dogs are well-known for their ability to read their owner’s body language. On the flip side, people can also watch their pets for signs of distress.

Dr. Laura Robinson, Pawp veterinarian, recommends keeping an eye on the sounds and posture of the dogs. She says, “Variations in a dog’s sounds and body language are a good indicator of their intentions. An aggressive growl is accompanied by snarling, snapping, raised hackles, and a tense body and posture. Playful dogs may growl, yelp, or whimper, but their body will remain relaxed and loose.”

Keep their resting and sleeping areas separate

Dogs need their own resting and sleeping spaces, whether that be a bed or a crate. You should never get it mixed up that they can share; your dogs both deserve to have a space where they feel comfortable and safe. 

Having two separate resting and sleeping areas will be helpful to solve this problem. In addition, this will remind the dogs that there is enough for everyone to go around. Let them know that they do not have to feel threatened or competitive with each other. 

Reward them with treats

When your dogs demonstrate any sort of positive behavior when they interact positively with each other, you can reward them with treats. They are easy to give your dogs when they do something positive, and they help reinforce the idea that when they engage in such behaviors, they get attention. 

How long should I wait for the older dog to get used to the new puppy?

When you introduce your new dog to your older dog, you should not rush to conclusions regarding their compatibility of living together. Instead, practice patience; it can take up to a month for your two dogs to get acclimated to each other. 

Therefore, you might be worrying yourself for no reason if you panic they’re still not getting along, and it’s not a month since you brought your latest addition home yet.

If you follow the aforementioned steps and practice being patient, you can feel much more confident about your puppy and older dog’s odds of working out as housemates and, maybe someday, even friends. 

What should I do if they’re not getting along?

If your dogs are still not cooperating with each other and it’s been an entire month, it’s time to come up with some next steps.

The first thing that you can do is take both dogs to the vet to ensure that there’s not something physically wrong with them that is causing them to be cranky and aggressive.

You can always reach out to Pawp’s vets and pet experts; they’re available to assist you 24/7, and you don’t even have to leave the comfort of your home for an appointment. 

The veterinary professionals at Pawp can assist on behavior issues and may even suggest a professional trainer or behaviorist that would be helpful for your dogs to see. It can be frustrating when you believe you have followed the steps above correctly and there is still aggression demonstrated by both or either dog. But with professional help, you will be one step closer to an answer.

It will take time for your dogs to get used to each other

It’s normal for your older dog to feel a bit violated when you bring a new dog into the house, and sometimes puppies, with their lack of manners, can be a bit inconsiderate to their seniors. That being said, it’s possible to find peace between your two dogs, especially if you start by introducing them correctly. 


Introducing a New Dog to Your Current Dog | OSU Indoor Pet Initiative  

Introducing your new dog to your other dogs | Humane Society   

Doggie Social Hour | Tufts 

The Responsibilities of Pet Ownership | Texas A & M Veterinary Medicine

New Pet | Washington State University  

Dominance in Domestic Dogs: A Quantitative Analysis of Its Behavioural Measures | US National Library of Medicine 

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