Anyone else’s adult dog getting aggressive with a new puppy?

So, I’ve got this 5-year-old Shih Tzu, and a few months ago we brought a new puppy home. Now, the older dog gets pretty aggressive when the puppy gets close. If the puppy is just playing on her own, he’s fine, but the moment she tries to approach him, he snaps at her. He’s even afraid of her sometimes, which is odd because he’s usually pretty stubborn. I’ve been trying to manage it by holding both of them at the same time, but no progress after 3 months. Anyone else been through this?

Same here! My older dog wasn’t a fan of our new puppy at first either. I think it’s just a matter of getting them used to each other. Have you tried keeping them apart and letting them meet slowly? My vet suggested that at first, and it helped a little.

@TrainYourTail
What do you mean by ‘letting them meet slowly’? How did you do that?

Linda said:
@TrainYourTail
What do you mean by ‘letting them meet slowly’? How did you do that?

Oh, sorry, I meant like, allowing them to interact through a barrier like a playpen or gate. They can see each other but not get too close, so it gives them time to adjust without being overwhelmed. Eventually, we let them meet face-to-face in short bursts, with supervision.

I read that sometimes the older dog gets possessive or just doesn’t like the puppy’s energy. Maybe try walking them separately first so they both feel comfortable before being around each other? Keep them leashed at first to control the distance.

@DogLoverDave
That sounds like a good idea. I’ve mostly just been letting them roam together, but separating them for walks might help. Thanks!

Have you thought about doing some training with them together? I know it can help show who’s in charge. I started doing it with my dogs, and it seemed to calm things down. I’d recommend working on some basic commands like ‘leave it’ or ‘sit’ to get them focused on you.

@HenryIsaak1
Yeah, I’ve been working on ‘leave it’ with both of them, but still not much progress. Maybe I need to be more consistent with it.

It’s tough, especially when the older dog is already used to being the only dog in the house. Try not to rush their interactions and let the older dog adjust at his own pace. He might be feeling like his space is being invaded.

@BenjaminYoung
Yeah, that’s a good point. He’s always been the center of attention, and now there’s this little one running around. Maybe I need to give him more space.

If he’s afraid of her, maybe it’s worth getting a temperament test to see if there’s something else going on, like possession aggression. My vet suggested that when I was dealing with similar issues.

Kajol said:
If he’s afraid of her, maybe it’s worth getting a temperament test to see if there’s something else going on, like possession aggression. My vet suggested that when I was dealing with similar issues.

I didn’t think about that! I’ll look into it. Thanks for the suggestion.