This family's finally all together. For the first time, 18-year-old Gavin Harding meets his son, William and holds his baby in his arms. His fiance, Melissa, gave birth to William while Gavin was away training to become a Marine. Gavin and Melissa met in grade school and are set to be married in just a few days, before Gavin heads out for more military training. InsideEdition.com's Leigh Scheps (http://twitter.com/LeighTVReporter) has more.