A boy and a doctor were fishing a boy is the doctor's son but the doctor is not the boy's fatherwho is the doctor?

The doctor is the boy's mother. When telling this riddle, many listeners will automatically assume the doctor is male, and this is what makes it so difficult to solve. This is likely for a few reasons - many unknowingly stereotype doctor as a male profession, as well as the hobby of fishing. The mention that the doctor is fishing with a son, also subconsciously implants the male gender in the listener's head on top of it.