How can I make my guinea pigs to stop fighting each other?

I bought two baby guinea pigs on Saturday. They were fine on Sunday and then Monday night a couple hours ago I noticed they’re fighting each other. No harm has been done yet. I don’t really want to separate them since they’re brothers and they’re social animals, but if there is no other way to stop the fighting then so be it I will separate them tomorrow morning. I did give one of them a bath because he was covered in pee. Could the reason be why they’re fighting is because the one I gave a bath smells different? They also keep squeaking at each other and they didn’t do that before.
So please help with any suggestions or comments on to stop them behaving this way.