Sentence 1: Billy was happily playing with his toy truck in the street. 
 Sentence 3: Billy's therapist tried to calm the situation down 
 Sentence 4:  One of the cops shot the therapist 
 Sentence 5:  He later apologized, explaining he was aiming for Billy 
 Option 1: Someone called the cops on the autistic adult. 
 Option 2: Someone came to play with the autistic adult.