I have had boy rats for about four years and never had too many issues with escaping or introductions. I recently however had my last unneutered male pass away and decided to take the opportunity to try girl rats (Buffy and Illyria). My first impressions were that they definitely had more energy and motivation to get into trouble than baby boy rats ever did. I adopted them at around 5 weeks (I usually prefer to get rats between 6-8 but they were rescues). Immediately I noticed that they were super friendly and not skittish at all. I kept them in an aquarium for three weeks separate from the boys and then began introductions. Immediately they clicked with one of my males (Reepacheep) who had been neutered young and overall was relatively friendly but the old man of the group (Spike) having just lost his brother was aggressive even after three bathtub introductions. Anyways, flashing forward they are now about two months. Reepacheep switches between living in the Ferret Nation at night with Spike to living with the girls in their cage during the day. I switch him over whenever I feed them. The girls being young have gotten into plenty of shenanigans so far from escaping their aquarium during quarantine by throwing off the lid to literally chewing through the bottom part of their current cage and getting out at night. As they get older they seem to get more rambunctious. Twice now in the last week I have woken up to them cuddling with Spike in the boys cage (they are still tiny enough to squeeze through the bars of the ferret nation). I don't know where this leaves us with introductions. I have just finished covering the Ferret Nations bars with chicken wire to prevent future escaping. Am I able to mix them together safely or should I start back with neutral territory?