During the first half of the circus scene, actress Brenda/Wendi Turnbaugh (Grace Ingalls), is absolutely sobbing, as actress Karen Grassle (Caroline) tries in vain to comfort her. The scene plays out to look as though Grace is supposed to be afraid of something at the circus. If you look at her, though, she's clearly not looking at anything going on in the ring, but in an offstage direction. I seems safe to assume that the goings-on during filming this noisy, visually overstimulating scene scared the little girl, and that she was crying for her mother or guardian, who would have been off to the side during filming. Grassle seems to be improvising (understandably) the script by saying things like "Oh, look at the clowns," and pointing to the ring continuously, in an effort to make Turnbaugh more compliant. Even more interestingly, this is not the last time that we see one of the Turnbaugh twins crying hysterically on camera. There were episodes in Seasons 7 and 8, in which Grace's evident distress was caught on film.