First Aired: November 18, 2007
Plot: The Griffins attend a Veteran's Day parade where, after listening to Herbert sing "God Bless the USA," Peter realizes he is proud of his American citizenship. He begins showing off his patriotism everywhere he goes, even going as far as buying a suit themed after the American flag. He also becomes frustrated with the presence of illegal immigrants, especially with the fact that they are taking away good jobs. Peter goes to great lengths to make Quahog immigrant-free, such as patrolling the town border and banning all non-American influences from his house (much to his family's chagrin). At the brewery, Peter convinces his supervisor to initiate an inspection, laying off any immigrants employed. After doing so, he goes to his mother Thelma's house for his birth certificate to prove his citizenship. However, Thelma tells Peter a startling secret: he was born in Mexico, not America!
She explains that after learning she had been impregnated by an Irish drunk, she went to Mexico to get an abortion; however, she was forced to wait until Peter was born. As soon as he was, she immediately realized she loved him and took him home with her. Not wanting to risk exposing his existence while crossing the border back to America, she never filled out his citizenship papers; as such, Peter himself is an illegal Mexican immigrant.
Peter is subsequently unemployed and the family begins to fall into debt. Lois suggests that Peter try to take a naturalization test. He fails, however, and he and Lois are informed that their marriage, which has lasted for 20 years, may not even be legitimate.
After Peter fails to find any good jobs, Lois turns to her father Carter for assistance. Carter agrees to employ Peter as a servant on his estate, and the Griffins move into a settlement of other Mexican immigrants near Carter's mansion. Of course, working as a servant, especially under Carter, proves grueling for Peter, who begins to empathize with the immigrants. He forms a friendship with them, and they in turn invite him and his family to a party to celebrate Cinco de Mayo. However, Carter crashes the party by reminding him of American regulations. Peter is outraged and rallies up the immigrants to form a rebellion. Carter decides to negotiate with Peter, saying he will grant him American citizenship if he calls off the rebellion. Peter demands that everyone must gain citizenship, but the others insist that he take this opportunity, saying that their day will come someday. Peter agrees, and from this point onward Peter becomes an official American citizen; the family moves back to their house, Peter regains his job, and all is well.