Truly's sister, Milly, is played by Liza Weil, who played Paris on Gilmore Girls, another show by ASP
Carl's mother, Sweetie, is played by the same actress who appeared as the harpist Drella In "Gilmore Girls", and who went on to star as agent Susie Myerson in the Amy Sherman-Palladino show "The Marvelous Mrs. Maisel".
The Chinese restaurant where Boo meets Carl's parents is an actual restaurant in L.A.'s Chinatown, named Hop Louie.