Born into a prominent Mormon family in Utah, Laraine Day's acting career began after her parents moved to Long Beach, California, where she joined the Long Beach Players. She appeared in her first film in 1937 in a bit part, then did leads in several George O'Brien westerns. Signing a contract with MGM, she achieved popularity playing the part of Nurse Lamont in that studio's "Dr. Kildare" series. An attractive, engaging performer, she had leads in several medium-budget films for various studios, but never achieved major stardom. She was married for 13 years to baseball manager Leo Durocher, and took such an active interest in his career and the sport of baseball in general that she became known as "The First Lady of Baseball".