Nancy Blair (defendant) conceived a son in 1976, during a time when she was having sexual relations with her husband and two other men, including William Blair (plaintiff), with whom she had a one-night stand. William saw Nancy soon after the child, Devin, was born, but they did not discuss paternity at that time and went their separate ways. In January 1979, Nancy informed William that Devin was his son. William met them both and then he and Nancy resumed a relationship. She separated from her husband that spring and in the following year gave birth to a daughter fathered by William. After Nancy’s divorce was finalized at the end of 1980, she and William married. He adopted both children. In November 2001, Nancy filed for divorce from William. William cross-petitioned for an annulment on the grounds that Nancy had induced him to marry her through fraud: it turned out that he was not Devin’s father as she had claimed. At trial, William testified that he never would have seen Nancy again had she not lied to him about Devin. Consequently, he would not have married her. He admitted to falling in love with her after resuming their relationship, however. The trial court rejected William’s petition for an annulment, and he appealed.