"Leap Day" is the 17th episode of the third season of the American sitcom Modern Family, and the series' 65th episode overall. It aired on February 29, 2012. The episode was written by Danny Zuker and directed by Gail Mancuso.

It is February 29, a.k.a. Leap Day, and it is also Cameron's (Eric Stonestreet) birthday. He is turning 40, but as his birth date, being Leap Day, only occurs once every four years, he likes to think he is turning 10. Mitchell (Jesse Tyler Ferguson) is extremely pressured to arrange the perfect party for him and has planned a Wizard of Oz-themed party and sets everything up while Cameron is away. However, when Cameron comes back home, he tells Mitchell that he will be busy for most of the day talking to his family in the aftermath of a tornado that hit his hometown. Realizing the Wizard of Oz is famous for a tornado, Mitchell abruptly cancels the Wizard of Oz-themed party and is forced to come up with a different party idea within a couple of hours.

Meanwhile, Phil (Ty Burrell) is especially excited about Leap Day that he takes the day off from work to do something fun with his family. Claire (Julie Bowen) decides to sign the family up for a trapeze class at a local amusement park. However, Claire gets on her menstrual cycle and Phil gets horrified when Haley (Sarah Hyland) and Alex (Ariel Winter) get on their cycles as well. Thinking their moody behavior will ruin his day, Phil conspires with Luke (Nolan Gould) and Manny (Rico Rodriguez) to go to the trapeze class without the girls, telling the boys not to mention the cycle. Phil has Luke pretend that he is similarly feeling under the weather like the girls, but this backfires as Claire insists Luke stay home, prompting Manny to go home. Phil decides to have Luke feign a cut on his finger using fake blood so they can have an excuse to leave the house to go to the doctor. Luke accidentally spills most of the container on himself. When Claire finds the container of fake blood, Luke is forced to admit that Phil wanted to leave the girls home due to their menstrual cycles (which he mispronounces). All three women are disgusted and Claire berates Phil.

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