A boy was getting a checkup at the doctor's office, while his mother was in the waiting room. Trying to get some information out of the boy, the nurse asked, "What's your mother's name?"
The boy replied, "Mom."
The nurse said, "Well, what does your dad call her?"
The boy responded, "Tammy." The nurse wrote this down. She did the same thing, only with the father as the subject, and got the same reply, "Dad."
As a last resort, she remarked, once again, "What does your mom call him?"
The boy looked up at her with big innocent eyes and said, "Idiot."