Oprah's travel budget just took a pretty big hit -- TMZ has learned several members of the 21-member polygamist family from "Sister Wives" just rolled over to Chicago to tape a spot for O's TV show.
Sources connected to the production tell us Kody Brown, his multiple wives and "some" of his 16 children blew into the Windy City a few days ago to be interviewed by the Queen of Daytime for an episode set to air next week.
Oprah's no stranger to the topic -- just last year, she interviewed another polygamous family during an entire hour dedicated to exploring the world of plural marriages.
YOU get a wife! YOU get a wife! EVERYBODY gets a WIFE!