Yeah, my last cat that had kittens--this was years ago when I was in college--moved her family three times within the first four days. Their instinct just tells them to move the little babies in case predators might be hot on their trail. We kept finding new little nests in places like the back of the laundry closet, the back corner of the kitchen pantry, etc. Finally when the kittens got more mobile and their eyes were fully open, she quit trying to relocate the whole family. Or else it finally clicked and she realized she was inside a house away from any predators or potential kitten-killing male cats.