Let's Go Fly a Coot

Glenn Close as Mona Simpson
Carice van Houten as Annika Van Houten

"Let's Go Fly a Coot" is the twentieth episode of the twenty-sixth season of the American animated sitcom The Simpsons, and the 572nd overall episode of the series. It first aired on the Fox network in the United States on May 3, 2015. The episode's title is a parody of the song "Let's Go Fly a Kite".

The Simpsons are invited to Milhouse's birthday party, which is shown to be a big expensive party, so much that Kirk has to sell the house in order to pay for it. When Marge and Homer think that all birthdays are getting too expensive, Homer takes drastic measures by ruining other kids' big birthdays; however, the party committee discover Homer's deeds and at first put a black mark on the Simpsons, preventing Bart, Lisa and Maggie from ever having another birthday party, but Homer is given a deal to make sure the kids can have one again. Homer must give Rod a magical birthday party or the black mark will remain (that and Bart threatens to wake Homer up on Saturdays with pots and pans). When the party takes place at the Springfield Air & Space Museum, the Simpsons are surprised when one of the veteran pilots being honored at a ceremony recognizes Grandpa and tells them of Homer's dad's service with the pre-USAF air command services during World War II. The veterans aren't happy that Homer and Grandpa are estranged and actively intervene in the relationship, forcing Homer to hug Abraham at gunpoint. Grandpa eventually reveals that he was in love with a waitress at the main diner near the base but wasn't brave enough to attract her attention, so he stopped his regular maintenance job and took a supersonic flight that nearly killed him but won over the waitress—who was Mona, Homer's mom.