I introduced my new 9 week old female guinea pig Amy to my other 2 females. One is Chloe about 6 months old and was a mommy(bought her pregnant), I kept one of her sons. Had to adopt out the other one. My other guinea pig Bella is about 1 1/2 years old. I was thinking that Chloe would be extra sweet to her and Bella, since she is the dominant one would be more mean to her. I was wrong. Chloe is being the mean one to her. She chases her around the cage and bites at her(no blood) and Amy squeals. Bella has intervend a few times as if to say to Chloe “stop.” To day has been better than yesterday. I put Chloe and Amy in a bath together. I havn’t heard any loud squealing, but Chloe has still chased her around the cage a few times. Amy tried to hide(usually on top if the hay rack where Chloe can’t get her. Amy just kind of sits there. She has lit up a little bit and drank some water when Chloe and bella were sleeping together. I havn’t seen her eat any pellets yet though. She does eat hay and I have few her some veggies. I am not sure if this is Chloe being dominant, mean, or jealous. My cage is 16 square feet and I have 3 food bowls and 3 water bottles and 2 big hay racks.
I think it is hard sometimes, I’m going through something like that too. it could be a personality thing. as long as they have to get away from each other. they could start to get along. just watch Amy, she might get stressed out. my girls are starting to get a bit better. I also find that when there is a age difference there will always be a personality difference. good luck!!!!