Older dogs can be stubborn, they have a set routine in their territory. A new puppy can have seemingly boundless energy, this may disrupt your older dogs' normal routines. That can cause mental and even physical harm to your senior dog. Gauge your older dog’s temperament, if your senior dog is territorial, they may have a harder time sharing. If they’re a big dog who throws their weight around, that could prove harmful to your puppy. If the older dog is a small breed, the puppy might harm them while they learn to play. Research your breeds to determine if blending them together is a good fit.
Follow your dog’s lead, some dogs may warm up to one another faster than others, that’s okay. Being patient and waiting for your dogs to make the first moves will promote a safer, more relaxed space for them to become acclimated. Watch body language, your dog will show how they’re feeling with their whole body, keep an eye out for posturing, fur standing on end, growling, or aggressive staring. If you notice this type of behavior, calmly direct their attention elsewhere. Set boundaries, like any healthy relationship, establishing boundaries with your dogs will help them avoid territorial behavior. Each dog should have its own toys and belongings. To relieve your senior dog’s anxiety, you may need to focus on them a little more.
Start during the socialization period, the age of your puppy will make them more susceptible to adapting to your senior dog. Your senior dog’s established routines will be difficult to change, but a puppy between 2 and 4 months of age accepts new people, places, and animals more easily. Provide verbal feedback, as in other training scenarios, verbal feedback when your dogs are meeting will help direct their behavior. Positive feedback when they’re acting appropriately will encourage that behavior. Negative feedback when they’re behaving badly, even something as small as “Cut it out” in the right tone, will help to curb bad behaviors.