Katie Mitchell, the teenage aspiring filmmaker protagonist voiced by Abbi Jacobson, is explicitly depicted as lesbian through multiple on-screen elements including a rainbow pin, a home movie of her asking a girl named Chloe to prom, drawings of and references to her crush Jade, and a final scene where her mother asks if she and Jade are 'official' yet. Creators Mike Rianda and Jeff Rowe, along with producers Phil Lord and Christopher Miller, deliberately wrote Katie's queerness into the script as a priority, using a tearful letter to convince Sony executives and framing it in Q&As as advancing queer representation in family animation.

This representation is prominent for the lead character in a PG-rated film aimed at children and families but remains secondary to the robot-fighting and family-reconciliation plot rather than driving the premise or emotional core. Reception includes praise from outlets for matter-of-fact LGBTQ inclusion alongside some audience criticism labeling the handling clumsy, with no widespread casting controversies or source-material alterations involved.