02E19 - Good Girls

Ray wonders why Marie is suddenly good friends with Robert's girlfriend Amy. Then Frank lets the cat out of the bag and tells him that Marie likes Amy more than Debra. Ray and Debra later find out that the only reason Marie likes Amy so much is because she hasn't had sex yet and is saving herself for the right person. During the discussion, it comes up that Debra wasn't exactly a "good girl" before she got married. When Debra argues for her side, Frank blurts out that Marie wasn't exactly a "good girl" either. That's when the viewer finds out that Robert was conceived illegitimately. Apparently Frank and Marie had been lying to Robert all these years about his real birth date. As it turns out, that current day was his real birthday.