It's hard to believe that it's only been four years since Little Mix won theThe X Factor.
The girls first celebrated their anniversary by giving an epic performance on the Today show.
Even their smallest fans got in on the action.
They even treated the crowd to an a cappella version of "How Ya Doin?" complete with beatboxing from Jesy.
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The girls then gave an intimate concert for AOL Live from 30 Rock.
They were presented with a video montage from friends and family, causing Leigh-Anne to cry so hard her false eyelash fell off.
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The girls even got a little nostalgic, covering "ET" just as they had done on The X Factor during Halloween week.
Talk about a throwback! @LittleMix nostalgia on stage for #LittleMixAnniversary #BUILDseries 🎶
Sure, there may have been some tears.
Hearing her silently cry and try to hide it breaks my heart so much #PerrieWeLoveYou #LittleMixAnniversary
But like always, Perrie had her girls to back her up.
Here's to another four years of great music, friendship, and girl power.
Mixers! THANK YOU SO MUCH for being a part of today!! You're the best ❤️ #4YearsOfLittleMix xxLittleMix Xx
