My rats are housed in wire dog kennels, a small size for the girls(wrapped in hardware mesh) and a large size for the boys(with no hardware mesh-they are too big to fit through the bars). They have lived this way for months with no issue. I have 2 boys and 2 girls. This morning when I got up for work I saw the girls' door wide open. I paniced and woke my husband up, telling him the girls were loose in the house. We started looking around...then I saw a head poke out of the boys' box(that they use for a bedroom)...then 2 heads..then 2 more. And I said "call off the search, the girls were partying with the boys all night". I reached in and, instead of coming right up to me like normal, they all ducked back into the box. I literally had to pry both girls' paws off the bars(after a mad chase through the cage). Apparently they learned how to open the latch at some point last night and found the boys' presence rather comforting...and didn't want to leave. So now the girls have a lock on their latch and are settled back into their own home, accepting that I won. Now I'm worried that their little adventure may have been provoked by them being in heat and that in a little while I will have 2 pleasantly plump girlies to deal with. My question is, how do I know if they're actually pregnant? And really just...now what? The cages are more than big enough to support a growing family, but this is something we tried really hard to avoid. We just don't know anything about raising rattie babies or supporting a pregnant mom(or even how to tell if we have a pregnant mom or moms!).