Discovered by Hollywood director Frank Borzage at Dublin's International Horse Show
Was under contract to Fox Film Corp.
Feature acting debut, "Song O' My Heart"
Under contract with MGM, Culver City
Made first Tarzan film opposite Johnny Weismuller, "Tarzan the Ape Man"
Made first of six films at MGM with journeyman contract director Richard Thorpe, "The Voice of Bugle Ann"
Journeyed to England to make an MGM film opposite Robert Taylor, "A Yank at Oxford"
Made last of six screen appearances as Jane in the "Tarzan" series, "Tarzan's New York Adventure"; was also last film for six years; retired from the screen to raise family
Returned to features as the female romantic lead in "The Big Clock", starring Ray Milland and Charles Laughton; film was directed by her husband John Farrow
Hosted the syndicated children's anthology series, "The Children's Hour", which presented hour-long films aimed at young audiences
Again left films after "The Wild Heritage"
Briefly a member of NBC-TV's "Today Show" team as the "Today Girl" (date approximate)
Acted in stage productions in the 1960s, including "The Front Page," "No Sex Please, We're British," and "Never Too Late"
Contributed short stories to various magazines
Returned to films to play a prominent role in the adaptation of the stage comedy, "Never Too Late", reprising the role she had played on Broadway
Appeared as Olive Whalen on the ABC TV daytime soap opera, "All My Children"
Made a cameo appearance as herself, along with many other well-known personalities of the 1930s and 40s, in the film, "The Phynx"
First TV-movie, "The Crooked Hearts"; acted in support of Rosalind Russell and Douglas Fairbanks Jr.
Returned to Broadway to play a prominent supporting role in the acclaimed revival of Paul Osborn's 1939 play, "Morning's at Seven"
Began appearing occasionally in features again after a decade absence: made only non-US feature credit other than "A Yank at Oxford" (1938), "Traveller", a film co-produced by Ireland and the UK
Played mother of Mia Farrow in Woody Allen's "Hannah and Her Sisters"
Final film role, "Stranded"
Final screen acting role in the NBC TV-movie "Hart to Hart: Home Is Where the Heart Is"
Was played by actress Heidi von Palleske in the biographical TV miniseries portrait of O'Sullivan's daughter, "Love and Betrayal: The Mia Farrow Story"
Was an interview subject for the A&E series "Biography" in episodes on Jean Harlow and Tarzan creator Edgar Rice Burroughs