Homer's Paternity Coot

Michael York as Mason Fairbanks
William H. Macy as himself
Joe Frazier as himself

"Homer's Paternity Coot" is the tenth episode of The Simpsons' seventeenth season. It first aired on the Fox network in the United States on January 8, 2006. Mail from forty years earlier is discovered, and a letter from Homer Simpson's mother's old boyfriend states that he is Homer's true father. Homer sets out to find his new father, leaving Abe Simpson behind. It was written by Joel H. Cohen and directed by Mike B. Anderson. The episode guest stars William H. Macy and Joe Frazier as themselves, and Michael York as Homer's new father, Mason Fairbanks.

As Marge goes shopping, a toll booth appears, but Marge and other Springfield residents take "The Ol' Cheapskate Trail". Mayor Quimby enforces tire spikes and blocks off the escape route because he desperately needs the money in order to “de-python” the town fountain. The next time Marge comes up to the booth, she backs up, causing many cars' tires to become severely damaged. The tires are thrown in the tire fire, melting ice on Mount Springfield and revealing a mailman which has been frozen for 40 years. His latters contain many revelations (Dewey Largo never knew he was accepted into a prestigious music program, and Moe never had an allergy that kept him inside for most of his childhood) and one of the forty-year-old letters is delivered to Homer's mother, Mona Simpson. It is from her old lifeguard boyfriend, whose name begins with an M, who writes that if Mona replies to the letter, she has chosen him, and if she does not, she is choosing to stick with her husband, Abe. He also writes that either way, in his heart he knows that the baby she is carrying is his.