T.S.
Hi M.,
This is not "normal" but not particularly serious either. I am an osteopathic physician and see this frequently in babies.
There are more than 20 little bones in the head and she has what is called in osteopathic language a "cranial torsion" putting a small amount of pressure on the nerve that goes to one of the muscles in her neck called the Sternocleomastoid (SCM). This can easily and painlessly be corrected by someone who is trained in cranial osteopathy or craniosacral therapy. Here are a few links for more information and to find a doctor/therapist in your area.
http://www.cranialacademy.com/
http://www.academyofosteopathy.org/
http://www.upledger.com/
Dr Sherri T.
Cleveland, Ohio
www.osteomed2.com