Okay, so I have had my guinea pigs for about 5 months now. Their names are Milo, and Pippin. They have lived together since they were a couple weeks old. I adopted them from a older lady on craigslist when she no longer wanted them. I got them a bigger cage, 47" by 24" Midwest Guinea Habitat. But after a couple months they started getting into mini fights. After a while, I separated them for now almost 3 weeks, because I neutered one to see if possibly he would stop being aggressive. Which I know it usually doesn't help, but he also had a medical condition and needed to be neutered anyway. But 2 weeks after the of Milo's surgery he and Pippin would chatter, squeak, and rumblestrutt at each other, even between bars. I was wondering if any of you have experienced this and how you handled it. I have heard of bathing them together, and sometimes it helps. I have done some meetings in their 5ft long playpen, at first they get along, but after a while they start the rumblestrutting again. I'm worried to keep them together when I'm not standing above them and on guard. Thank you!