Olivia Falconeri is Kate Howard’s (Connie Falconeri’s) cousin. They both grew up in Bensonhurst and knew Sonny from the neighborhood. Growing up, Sonny was known as the bad boy of Bensonhurst. When Sonny wanted to surprise Kate on her wedding day, he went to Bensonhurst and asks Olivia to come to Port Charles to attend the wedding. Olivia agreed.
Once in Port Charles, it is clear that Olivia and Sonny have a past. It is revealed that Olivia dated Sonny for a brief time when they were teenagers and Olivia became pregnant with Sonny's child. She never told Sonny about his son, Dante Angelo Falconeri. She felt that Sonny's ties with Joe Scully and "running numbers," in the neighborhood was too dangerous.
Olivia had a falling out with Kate, because she disagreed with Kate's decision to change her name and go to Manhattan for a career in fashion. But Olivia swore Kate to secrecy about Sonny's son. In Port Charles, Olivia vows to keep her secret from Sonny, feeling his life in the mob is too dangerous for her son.
When Sonny finally finds out Dante is his son, he is in total shock. He is angry at Olivia for denying him watching his son growing up. But Olivia insists she made the right decision. Sonny wants to know as much about his son as he can, but Olivia is not very forthcoming. Sonny is frustrated and sad that he missed so much of his son's life.
Olivia and Sonny continue their lifelong friendship as they share their love and concern about Dante.
Olivia and Sonny get close as they deal with some hardships. When Connie is murdered, they both turn to each other and make love together.