Henry James Herman is a genius.
Raised by a loving, left-wing feminist mother, Patricia Herman, Henry, at nine months, is speaking in full sentences. At the age of ten he goes to college. But even a genius needs a father. So much to his Henry's Grandpa STAN reveals that Henry is a test-tube baby, and that he has uncovered the identity of Henry's biological half-sister - Audrey O'Hara (12). Audrey is the test-subject of her father's bestselling book, "Born Gay or Made That Way?"
While speed-reading the book, Henry meets the book's author, Audrey's father, DR. Slavkin O'Hara. Henry asks Slavkin why he once donated sperm, as he had stated in his book and Slavkin discloses that he was diagnosed with testicular cancer, and banked his sperm in the event that chemotherapy rendered him sterile.
As half-siblings with different mothers, the source of Audrey and Henry's common genes could have only come from one source right? However Audrey's mother had an affair with Slavkin's oncologist, DR Gunter Flowers, thus calling into question the identity of Audrey's biological father - Slavkin or his oncologist? The only way to determine the identity of their father is to get tested.
When the test results come in, Henry has finally found his biological father, Slavkin O'Hara, giving him the family he has longed for. Patricia, Slavkin, Audrey, and Henry make the best of this new opportunity they have been given, and our story ends with the foursome celebrating Audrey's thirteenth birthday, the first of many more birthdays for our (dys) functional family in the years to come.