Watch Demi Lovato and Paulina Rubio Perform "Girls Just Want to Have Fun" in Mexico

Demi Lovato is back on her Confident World Tour, and the "Body Say" singer made her Oct. 17 concert in Mexico City extra special by bringing Latin pop icon Paulina Rubio on stage for an impromptu duet.

The former X-Factor judges chose Cyndi Lauper's "Girls Just Want to Have Fun" for their reunion song, and, yes, it was amazing. Paulina shared a clip of the moment on Instagram, penning a bilingual caption to go along with it. "Gracias por la invitación @ddlovato, I love you little sister! Thanks to all the crew! See you soon little sis! Girls just wanna have fun!" she wrote. Press play above to see the snippet for yourself, then take a look back at Demi's Hollywood evolution.