MODERN FAMILY - "The Last Walt" - Claire delicately helps Luke cope with the fact that his friend and their old neighbor, Walt, has passed. Phil takes Alex for some father-daughter bonding time, and Haley throws an unauthorized party. Meanwhile, Jay and Gloria go over to Mitch and Cam's to have dinner with Cam's father, Merle, who is in town visiting -- and awkwardness and tension seem to be the rule of the night -- on "Modern Family," WEDNESDAY, APRIL 18 (9:00-9:31 p.m., ET), on the ABC Television Network. (ABC/PETER "HOPPER" STONE) BARRY CORBIN