MODERN FAMILY - "Leap Day" - Cameron's birthday falls on Leap Day, and with opportunities to celebrate so few and far between, the pressure for Mitchell to get it right is exceptional. Meanwhile, Jay's machismo is in question, and Phil's plans to observe the Leap Day holiday with the boys is thwarted by the girls, on "Modern Family," WEDNESDAY, FEBRUARY 29 (9:00-9:31 p.m., ET), on the ABC Television Network. (ABC/PETER "HOPPER" STONE) JULIE BOWEN, SARAH HYLAND (OBSCURED), TY BURRELL, ARIEL WINTER