@Brucker what kind of aggression? Is the puppy going after the older dog or is it one way?
I have only posted the fun photos but there have been some tense moments between these two here. It baffles me that they have zero food aggression and will share bowls randomly.
There have been some arguments over space and toys. At first Macallan was not allowed in any dog beds. Now he is with a "dont chew on my face" restriction.
To me this is a normal interaction where the puppy is learning the house rules, which the older dog gets to set. We have about 10 of these a day over various rules Macallan has broken. Dont chew on me, dont bother me when im sleeping, thats my toy, ect.
photos.app.goo.gl
Talisker likes to remind the new guy that when he wants the antler it is his, and not for sharing. Its part of them establishing a pack order. You can see him keeping his distance and acting super submissive as they get closer. Talisker has been around quite a few other puppies and I trust him to bark and not bite. Different with every dog. Neither of these guys are neutered which makes it a bit more important for them to establish the rules early. Talisker has quite a few male dog friends in our previous and current neighborhoods that are also intact males. We have never had aggression problems other than some chest beating. I attribute that to lots of early exposure.
Now we are slowly getting better. As long as these interactions are supervised I think they are productive. Puppies do not know how to communicate well and it frustrates older dogs. Add that on top of a suddenly shared space and it is normal to get some tension. Imagine getting a new surprise roommate who does not speak english, has ADD, no manners, and generally acts like he just smoked some crack.
I am not a dog trainer. Just my observations introducing lots of puppies over the years. Between our dogs and my parents I have watched the new puppy process for around 30 years now.