The third season of "The X Factor" U.S. has a two-part premiere, which Fox will televise on Sept. 11 and Sept. 12, 2013.
In 2013, the judges on "The X Factor" U.S. are Cowell, Lovato, Kelly Rowland (who replaced Britney Spears) and Paulina Rubio (who replaced Antonio "L.A." Reid).
Lovato commented during her interview with Fallon: "Both of them, Kelly Rowland and Paulina Rubio have become older sisters to me. They've helped me through so much, and we're always there together."
Not surprisingly, there was no mention in the interview about the alleged nude photos of Lovato that are reportedly being shopped to tabloids. Lovato has not publicly commented on these photos.
Meanwhile, even though Lovato won't be doing a full-scale tour in 2013 to promote her fourth album, "Demi" (she's too busy with "The X Factor" and her guest-starring role on "Glee"), Lovato has been doing some select performances this year, including at the Teen Choice Awards in Los Angeles, the MuchMusic Video Awards in Toronto and Festival People in San Antonio, Texas.
On Sept. 20, 2013, Lovato will be one of the performers at We Day in Toronto. Then on Sept. 21, 2013, Lovato is doing a free show to celebrate the opening of the Microsoft Store at the Burlington Mall in Burlington, Mass.
Lovato tweeted: " I feel like Kenya is my home away from home... I wanna go back ASAP!!!! After my adventure in Kenya with @freethechildren I'm so happy I can attend #WeDay on Sept 20 in Toronto!"
As previously reported, Lovato spent her 21st birthday in Kenya on Aug. 20, 2013, doing charity work for the organizations Me to We and Free the Children.