My hamster's babies has white fluffy stuff on its skin...?

ok first let me tell you the story ... my hamster was pregnant and when i checked her cage on a saturday morning, she was gone!!! .... i checked everywhere but i couldn't find her. then i heard a munching sound (or something was chewing wood) behind my cabinet, then i checked there and she was there!!! ... The bad news is that she gave birth behind my cabinet.... i couldn't move it cause it was so heavy.... so i just left her there and i have just been leaving food and water on the corner of my cabinet (but i can still see the babies and the mom) ... The babies are 1 week old now and when i checked the babies there were white fluffy stuff on its skin ... its not really clear but i can see it .... can someone tell me what's the white fluffy stuff on their skin is??? (Again their 1 week old and the mom has been nursing them)........