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Demi Lovato and Selena Gomez are getting some time to mix business with pleasure. 

Selena was scheduled to perform on last Thursday's "X Factor," but was pushed back because of a voting glitch that forced a re-match for contestants.  Instead, Selena spent the evening with her longtime friend Demi Lovato, who is a judge on the Fox show. 

The two posted silly photos together from the set.  Demi captioned the photo with the hashtag "#14YearsStrong," calling it "the evidence of forever." 

Selena will return to the show to perform this week.  The Texas natives met as girls when working together on "Barney and Friends."  

Both have a busy year ahead.  Selena has been touring the country in support of her recent Stars Dance album, while Demi is currently guest-starring on "Glee" and is prepping for her own "Neon Lights" tour, which kicks off in February 2014.