Final answer:
Joe's condition is called prosopagnosia, also known as face blindness. It is a neurological disorder that affects a person's ability to recognize familiar faces. People with prosopagnosia often rely on other cues such as distinct facial features, unique characteristics, or voice recognition to identify familiar individuals.
Step-by-step explanation:
Joe's condition is called prosopagnosia, also known as face blindness. It is a neurological disorder that affects a person's ability to recognize familiar faces. While Joe is unable to recognize his wife and children by their faces, he can identify them by their voices. People with prosopagnosia often rely on other cues such as distinct facial features, unique characteristics, or voice recognition to identify familiar individuals.