Today is the birthday of Gracie Doll (Freida Schneider, 1888-1970), one of the quartet of four German midget siblings known as the Doll Family. Along with her brother Harry (best known for his roles in the Tod Browning movies The Unholy Three  and Freaks ) she began performing in German sideshows early in the twentieth century. The pair was billed as “Hansel and Gretel”. In 1914 American impresario Bert W. Earles brought them to the U.S. to be in the 101 Ranch Wild West Show. Daisy and Tiny joined them about a decade later, and for a time they all took Earles’ last name for their own (they changed it to “Doll” when Earles passed away).
For three decades they appeared with the Ringling Brothers, Barnum & Bailey sideshow. From 1956 to 1958, they appeared with the Christiani Circus; then they retired. All four of the siblings appeared in the movie The Wizard of Oz (1939). Daisy co-starred with Harry in Freaks and was also in The Greatest Show on Earth (1952).
Yes, you got it right. That romantically attached little couple in Freaks were played by BROTHER and SISTER. In the long run, this may be the creepiest thing about the film.