A doctor and a boy were fishing. The boy was the doctor's son, but the doctor was not the boy's father. Who was the doctor?
1 2
Comments  (Page 2) 
The Doctor was the mother
The boy is the doctor himself. Because at the beginning of the question it says a boy and a doctor WAS fishing, indicating that the boy and the doctor are the same person.
Teachers: We supply a list of EFL job vacancies
The doctor is the boys mother