The leading man looked debonair in a black Gucci suit with a white dress shirt and black tie. His mother was all dolled up in a black dress, a burgundy coat with multi-colored feathered shoulders and flashy sunglasses.
Cooper was nominated for two SAG Awards for his performance in the musical: Outstanding Performance by a Male Actor in a Leading Role and Outstanding Performance by a Cast in a Motion Picture.
While the A Star Is Born cast didn't receive any accolades during the night, Cooper, along with Lady Gaga, Sam Elliott and Rafi Gavron, took the stage to present their movie and snap photos between breaks.
There will be plenty more of the film's leading stars at the 2019 GRAMMY Awards on Feb. 10. “Shallow,” the lead single from the the official soundtrack, was nominated for Song of the Year and Record of the Year.
For now, see more of ET's SAG Awards coverage, below!