Demi Lovato, X-Factor Judge, Tweets Hilarious Simon Cowell #Throwback Pic

Demi Lovato's going to be on the X Factor Season 3 in September; the season's locked and loaded. But behind the scenes, a lot else is going on. Including hilarity with Simon Cowell.

Demi Lovato, Simon Cowell, Kelly Rowland, and Paulina Rubino will be judges on the X-Factor...and Demi, the outspoken 20-year-old singer, is picking on Simon on Twitter already.

Last week was Demi's birthday, and she wanted a Barbie that looked like her and represented real women. She spoke out about body image and Barbie on Twitter, saying Barbie should have cellulite, just like 95% of women do.

This week, though, Demi was lighthearted, Tweeting an old Simon Cowell throwback pic that's a winner...to say the least.

It might be, um, the best photo ever. Ever. Of all time.

Simon fired back in his usual dry, acerbic tone, telling Demi to cut it out in a very Simon way. He said,

Demi's apparently digging deep...because there's this gem also, from two weeks ago:

Well, well. Look at this ancient pic I found!! Same t-shirt, same middle part.. Recognize this @simoncowell??

When the X Factor officially starts, we'll have more of Demi Lovato and Simon Cowell snarking at each other...but for right now, this is way more than enough.