A massive search for a missing Lincoln County girl has turned up nothing. Now her mother speculates Bianca Piper has left the area. Shannon Tanner admits she has no reason to reach such a conclusion, just a gut feeling that Bianca no longer is in the area. Worry has increased about Bianca, because she suffers from bipolar disorder and attention deficit hyperactivity disorder. Without her medication she can become disoriented and may hallucinate. Bianca has been missing nearly a week.