Christina Applegate has been a dancer in real life, and starred in Sweet Charity on Broadway in 2005, so adding dance to her character made sense. Episode nine opens with her having a great time in dance class while Judy is simultaneously miserable while painting.
"There's only a mention of it one time, where she says, 'I wanted to be a dancer. It's stupid.' They wanted to have a moment where Jen's finally coming out of her pain, with dance," Applegate told Vulture. "Judy, on the other end of it, is now suffering. They wanted to find what would make Jen actually smile."
Applegate described the dancing as "horrific."
"It was so hard. It hurt a lot because I didn't have, really, any rehearsal," she said. "Our schedule is so tight that I had maybe one hour for us to choreograph. That was it. Then we shot it."