Abby Lee Miller gave two sets of students duets in “Dance Moms” Season 6, episode 9, but not all of her elite junior team members were happy with their routines.

In “Nia Save The Day,” Abby announces she will be giving her star pupil, Maddie Ziegler, and her team’s newcomer, Brynn Rumfallo, a lyrical duet. She also gives two of her “strongest dancers,” Kendall Vertes and Kalani Hilliker, a jazz duo titled “Grifters." During rehearsals, Kalani suffers a back injury and Nia Frazier steps in to fill her spot.

At the competition, Maddie and Brynn perform their duet flawlessly, even when their music cuts out mid-piece. With just one day to prepare for the event, Nia, 14, misses several steps onstage. After their performance, Kendall and Nia are reduced to tears backstage. Kendall cries on Kalani’s shoulder, saying she looked “so bad” onstage. Nia looks for consolation from her mother, Holly Frazier, who doesn’t mince any words.

“You didn’t let everyone down,” she tells her daughter. “I would be lying if I said I wasn’t disappointed. Of course I’m disappointed. You’re a better dancer than what was onstage.”

After Kendall confirms to Nia that she’s not angry with her — Kendall previously thanked her teammate for stepping up at the last minute — she and her mother, Jill Vertes, tell Abby their true feelings about the routine in the dressing room.

“You win, Abby. That’s what you wanted to do. You wanted to humiliate the girls and you did,” Jill tells Abby after she critiques Kendall and Nia’s performance. “It’s not fair to Kendall and it’s not fair to Nia that you put that onstage.”

As Kendall fights back tears, she reveals to her coach she felt she was “getting set up.” When Abby suggests the mother-daughter duo “get over” it, Jill reminds Abby she is responsible for what numbers she puts out into the world.

“I hope you’re happy with yourself,” Jill says.

“She’s very happy with herself,” Kendall responds.

Jill finishes her rant by asking Abby to give each of her students, not just her favorites, a chance to shine and “feel good about themselves.”

“I wasn’t put on this earth to make your kid feel good,” Abby responds. “I was put on this earth to teach her how to dance. Period.”

Abby later tells the cameras she thinks Jill has “lost her mind.” Abby claims that the previous day Jill was happy that Nia was filling in for Kalani but changed her tune after seeing Maddie and Brynn’s duet.

During the awards ceremony, Nia and Kendall earn second place overall for their teen duo/trio division. Maddie and Brynn place first in the junior division for “Together As One.”

“Dance Moms” airs Tuesdays at 9 p.m. EST on Lifetime.