I started keeping rats in Nov 2018 with 3 pew girls. In Dec i adopted 3 more girls. The first week of Feb i added 3 boys who were born on Jan 1st. On Aug 20th i then added 4 girls who were between 5 and 6 weeks old. And now becomes the "Uh oh and exciting" part. The girl i got these new girls from obviously did not seperate the boys and girls soon enough. First litter was on Aug 31 second litter was on Sept 4th. I am now a new "rat granddaddy" to around 25 kits. My rat family went from 13 to about 38 in 3 days lol. Not what i expected but it will be exciting watching the babies grow. I now need to build 2 more cages, yes i build my own cages, to seperate the boys and girls around 5 weeks. I will try to sell most but will keep a few. Fortunately i have the room and time to take care of, give attention to and play with all my rats.