Little Mix Go Back To Where It All Began... And Avoided A 'Nip Slip'

Leigh-Anne has the best sense of humor on the 'X Factor.'

Little Mix took a trip down memory lane on Sunday night. The quartet of divas returned to the "X Factor" stage, where they were formed more than four years ago.

Jade, Perrie, Leigh-Anne and Jesy performed together for the first time on Oct. 8, 2011 on the U.K. competition as Rhythmix. They've come a long way since then (starting with their Little Mix name-change) -- just look at the three albums (Get Weird comes out on Friday) they've released since then. When they hit up the show last night, they performed a mash-up of their songs "Love Me Like You" and "Black Magic."

Of course, the ladies slayed as usual, but Leigh took to Twitter to joke about a wonky part of their performance:

The moment she was referring to:

Totally could've been worse, but she still didn't miss a beat. What a pro!