So my partner and I got 2 boars 6 months ago, and all seemed to be well with them since we've had little to no issues with them. Then about 1 month ago, we decided to add a 3rd into the mix. We didn't have a big enough cage at the time, so we decided to keep GP3 in a separate cage next to GP1 & GP2 until we were able to fit them all in a single cage. The first time I did introductions, I got a bit worried when they were scuffling so I did separate the piggies (I know, should wait for blood but I'm still a new owner and it was scary). The next time, I let them work it out and only GP1 made any attempts to try and hump GP3 into submission, while GP3 just roamed around and did his own thing. After 4 hours of them not chattering or any of the sort, I decided to try and see how they would work living together and I placed them all in the cleaned out first cage. Within 10min, GP2 kept chattering at GP3 and lunged at him. I figured it was because of a small cage, so I took GP3 out and waited until my new cage (a 3x5 C&C cage) was built. I re-introduced them all in a neutral area, and it was, again, just GP1 trying to hump GP3 into submission and after a few hours it seemed like it worked out. After that, they were all placed in the new C&C cage and were quiet for the night. The next morning, I go to check on them and I see that GP2 would follow GP3 around and then start to chatter when GP3 stood his ground or yawned. This happens around food, toys, and even one of the hideys. A few times GP3 has even leapt at GP2 if he got too close while chattering. I looked at GP2's face and did notice there was a scratch/bite on his mouth, but more often than not it seems that GP2 is being the aggressor. GP1, during this usually, stays well out of the way but whines a lot. No blood has been drawn that I can see, all piggies are still eating, and if things get too tense then GP2 and GP3 usually just separate from each other. I'm not sure if this is just because they're all in their teen phase or if it's something to be concerned about.