Mom separated kitten, still nurses him?

My cat has 4 kittens that are 9 days old. This morning she moved 3 of them out of the basket (this almost sounds like a middle school math problem) and into the back of a cold closet on the concrete, so when I found them I moved them back. Just now she moved 1 of the kittens into the back of the closet (the one she didn't move before) and left the 3 in the basket. This kitten is not the runt, and acts very healthy. His eyes are beginning to open, he's crawling around and has a very healthy set of lungs. He cries when he's by himself. Everything I read said that cats move sick kittens so they don't get the others sick or they don't waste their milk on a kitten who is going to die. But she still feeds him when he is not with the others? I really want to call a vet but they are all closed and I don't know what to do.