I had two rescue litters born 3 weeks apart. I kept 3 girls from the first litter and I am keeping 1 girl from the 2nd. I want to introduce them, but I want to make sure that it will be okay to do this. The 3 girls are 8 weeks old on Sunday and 2nd lone baby will be 5 weeks old on Sunday. Should I hold off for a while even though she will be alone? Or should I try it out and see how it goes?