Hello all! I am new to guinea pig ownership. I am a teacher and have had a female guinea pig for 4 months in my second grade classroom. I just got a friend for her (a 2 month old female). The older one is showing dominance by chasing her around, showing her teeth by yawning (only periodically). She has mounted her a couple of times that I have seen, but mostly just follows her around, and seems to try to intimidate her a little bit. The little one squeals a lot when she does this, but doesn't seem too bothered. There has been no biting, no blood, and no real fighitng that I have seen. Is this ok, or is it stressful for the little one? They sometimes seem to get along, eat from the same pile of grass, etc. The little one "popcorns" a lot, so I am hoping she is happy? I have them in a large cage with a pen that is attached, with tunnels, etc., so they have plenty of room to run around. Thank you!