11 week old kitten tries to suckle off my skin., how to stop?

I have a very active healthy 11wk old kitten who is loving and all, but as she settles down she starts to suckle on my hand, arm, basically any exposed skin she can get to. Her two brothers don't do this, and they were all taken from mamma cat at the same time. She only does it at night, and it is most annoying when I am trying to sleep.