Dad sees a patient..

Dad and I are doctors. He had a patient that one day came in with a flea behind his ear. Week after week, said patient keeps returning to get this flea looked at. One day, dad goes on vacation, and leaves me in charge of the practice. The patient comes in, and in horror and disbelief of my dad’s incompetence, I immediately remove the flea, cure the wound and send the patient home, thankfully never to hear from him again. Upon my dad’s return, I’m delighted to rightfully pounce on him for the obvious oversight. He then proceeds to shoot back, that he’s been trying to keep the flea alive all this time, and since I obviously killed it, I can now begin to pay the rent for the practice.