Hilary Duff and Matthew Koma make pretty awesome parents, and their love story is equally as sweet. Before they became a family of five, they were two friends who couldn't stay away from each other. Once they decided to give dating a try, Hilary brought her son, Luca, to meet Matthew in an incredibly adorable way. Hilary shares now 9-year-old Luca with her ex-husband Mike Comrie. Although Matthew called their introduction "very casual" in a People interview, Hilary recalls the story as a precious moment between Luca and his future stepdad. "Matt was coming trick-or-treating with us and he w...