Well, after the usual sixty-plus days of pregnancy, your kitty will begin to act strangely. She will start snooping around, looking for the perfect place to bring her newborns into the world. Most set up a birthing box. This birthing box serves not only as a place for mother to have her kittens in, but a safe spot for her to care for them until they're old enough to run around on their own. This box should be in an out-of-the-way place that you can get to, if necessary, but where cat and kittens will have plenty of needed privacy. So, you might want to provide her with alternatives for the Litterbox. Good luck and you are soing a wonderful thing.