Donna, aged sixteen, lives at home with her mother, Martha, in Waupaca, WI, a state where the age of majority is eighteen. Martha is aware that Donna has recently exhibited a sometimes violent and delusionary nature diagnosed as schizophrenia and has attacked persons in the neighborhood. Medication that can control Donna's behavior has been prescribed, but without Martha's knowledge, Donna has stopped taking it. A week after Donna stopped taking her medication, she approached a neighbor, Peter, as he walked along the sidewalk fronting Martha's home. When she has a face to face with Peter, Donna, without provocation, gestured threateningly and screamed, "I know you're out to get me and I'm going to get you first," and then strode away. Peter, who had no knowledge of Donna's mental illness, phoned Martha about the incident. Martha told Peter that "Donna has sometimes made threats to others, but I do not think she will try to hurt you and I assure you that this will not happen again." Peter believed Martha's assurances and, for that reason, did not seek to avoid Donna. Martha questioned Donna about the incident, scolded her, and asked if Donna was taking her medication. When Donna said she was, Martha did not pursue the matter. Two days after Donna confronted Peter, Donna saw him raking leaves which had fallen into the street fronting their adjoining homes. Donna got on her bicycle and rode it as rapidly as she could directly at Peter. Although Donna swerved away from Peter