Maddie Zieglar, the 13-year-old dance phenom, performed last night with contestants on 'So You Think You Can Dance.' (Photo: ScreenCap)

Maddie Ziegler, the 13-year-old dance phenom, performed last night with contestants on ‘So You Think You Can Dance,’ raising new questions about pre-teen sexualization. (Photo: ScreenCap)

Maddie Ziegler, America’s first pre-teen sex symbol, performed last night on Fox’s “So You Think You Can Dance,” sharing the stage with other pre-teen and young-teen dancers as part of the show’s “Next Generation” finale. It raised new questions about under-age sexualization.

Ziegler gained fame on the Lifetime network’s reality show “Dance Moms,” which has been criticized repeatedly for over-sexualizing under-age girls.

But that didn’t stop Fox from dedicating Season 13 of its reality dance competition to “aspiring dancers” between the ages of eight and 13 years old.

Ziegler, who is now 13 herself, left “Dance Moms” this year and served as a guest judge on the show. She joined judges Nigel Lythgoe, Paula Abdul and Jason Derulo.

In her dance last night, Maddie was joined by this year’s Top 10 contestants: Tate, Emma, JT, Kida, Tahani, Ruby, Jake, Daniela, Jordyn and Sheaden. They ranged in age from 10 to 13.

They performed an interpretive dance dressed as forest fairies.

Maddie caused an uproar in January a year ago when she appeared in Sia’s “Elastic Heart” video, dancing with 28-year-old actor Shia LaBeouf. She was 12 at the time.

The video sparked a heated social media debate over whether the erotic interpretive dance routine, simulating a cage fight, was art, or merely kiddie porn.

Maddie wore a nude colored bodysuit and blonde wig; LaBeouf was stripped down to a pair of nude-colored shorts. Sia later apologized to anyone who was offended by what clearly were overtones of pedophilia.

Last night’s dance was Maddie’s second on the show. She and Travis Wall, who at 28 is more than twice her age, performed a contemporary dance last month.

Wall appeared on the show’s second season and now works as a dance instructor.

“Dance Moms,” that show that launched Ziegler to fame, was the subject of a petition drive two years ago to force Disney, which owns Lifetime, to take the show off the air.

“This show promotes children, girls as young as 8 years old, in blatant and overtly sexualized costumes and dance routines,” wrote Cynthia Tyler of Antwerp, NY, on her petition.

Check out Maddie’s performances below.

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