Lindsay-Hogg knew Welles, worked with him in the theatre, and met him at intervals throughout Welles's life. After he learned that Welles's oldest daughter, Chris, his childhood playmate, had long suspected that he was her brother, Lindsay-Hogg initiated a DNA test, which proved inconclusive. In his 2011 autobiography Lindsay-Hogg reported that his questions were resolved by his mother's close friend Gloria Vanderbilt, who wrote that Fitzgerald had told her that Welles was his father. A 2015 Welles biography by Patrick McGilligan, however, argues that Welles could not be the father: Fitzgerald left the U.S. for Ireland in May 1939, and was pregnant at the time she returned in late October, while Welles did not travel overseas during that period.