Pros and cons of getting another guinea pig?

I agree with the person above me. Since yours aren't very close, I don't think adding a new one to the bunch would be a very good idea. It's a possibility that maybe they would get along, but it's also a good possibility that they won't. They actually may hurt the new one because it'd probably be very small. So I would stick with the two you already have. Maybe if they start getting along you may want to consider it, but not right now! Hope I helped!(: