Jaafar Jackson rolled into Gary, Indiana -- the hometown of Michael Jackson -- for a special screening of "Michael" ... and it turned into a full-blown family affair! Check out the pics -- Jaafar was grinning ear to ear Monday night, hitting the podium for a speech and snapping it up with the rest of the Jackson clan ... including members of The Jackson 5. All smiles on the surface -- but not everyone showed up for the celebration at the famous Jackson clan's birthplace. Noticeably absent?