Kathryn Crosby (born November 25, 1933) is an American actress and singer who performed her most memorable roles under the stage-name Kathryn Grant.
Born Olive Kathryn Grandstaff in Houston, Texas, she graduated from the University of Texas at Austin with a Bachelor of Fine Arts in 1955. Two years later she became Bing Crosby's second wife after converting to Roman Catholicism for the marriage. She was 30 years younger than Crosby. The couple had three children, Harry, Mary Frances, and Nathaniel. She appeared as a guest star on her husband's 1964–1965 ABC sitcom The Bing Crosby Show.
She largely retired after their marriage, but did have a featured role in one of the most acclaimed motion pictures of the 1950s, the courtroom drama Anatomy of a Murder. She also played the part of "Mama Bear" alongside her husband and children in Goldilocks and starred with Jack Lemmon in Operation Mad Ball in 1957.