Gomez plays a tomboy whose family takes in Lovato's princess after a dictator invades her country. Gomez, who turns 17 this summer along with Lovato, says they bicker at first but eventually "realize that they complement each other."
Gomez says they fit their roles, since Lovato is more princessy.
While filming in Puerto Rico, Gomez says Disney tried to separate the duo at night by putting them in different buildings. But according to Gomez, she lived in Lovato's room "half the time."
"Princess Protection Program" airs June 26.
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