Ok, so I originally planned to purchase two 2X4 C&C cages for my two pairs of female guinea pigs, but I have decided that it would be best to combine the two cages (thus making it a 2X8) and put all four pigs together. Problem is; two of my pigs, Willow and Tilly, really dislike one another. They teeth chatter, rumble strut, and nip at one another whenever I allow them close contact, although as their current cages are right next to each other they seem interested when apart. Molly and Smokey, the other two, get along just fine, but I'm worried that if I combine herds, one of my girls is going to get hurt. Can I get any advice on how to introduce them without incident? Thanks!