Jennifer Lopez keeps having to remind Judy Robles that she deserves all the attention she’s been getting as the pair promote “Unstoppable.” The inspirational sports drama has been earning awards buzz, and at screenings, Robles has been greeted with standing ovations. Audiences are clearly impressed by how successfully this single mom raised her son, Anthony, despite having to endure financial hardships and an abusive relationship.

“I tell her all the time, ‘You need to own who you are and what you’ve done,’” Lopez says. “You’re inspiring every mother who has ever struggled. You really have triumphed. You’ve raised a son who has become a leader, and you deserve credit.’ But she’s very humble.”

Anthony, as “Unstoppable” watchers know, became a college wrestling champ, an improbable accomplishment given that he was born with only one leg. Judy was there on the sidelines, unexpectedly learning the same...