I just got two new chins, but was very worried about introducing them as this female, Ellie, is just a maniacal little fuzz butt, I love her anyhow, but I put the two together in the play pen, with it being separated in half, and she squeezed her way through hopping on top of the other and cuddling. It was chinchilla friendship at first sight. They won't be living together but at least she will have a play mate.