Welles credited "Rosebud" to Mankiewicz. Biographer Richard Meryman wrote that the symbol of Mankiewicz's own damaged childhood was a treasured bicycle, stolen while he visited the public library and not replaced by his family as punishment. He regarded it as the prototype of Charles Foster Kane's sled. In his 2015 Welles biography, Patrick McGilligan reported that Mankiewicz himself stated that the word "Rosebud" was taken from the name of a famous racehorse, Old Rosebud. Mankiewicz had a bet on the horse in the 1914 Kentucky Derby, which he won, and McGilligan wrote that "Old Rosebud symbolized his lost youth, and the break with his family". In testimony for the Lundberg suit, Mankiewicz said, "I had undergone psycho-analysis, and Rosebud, under circumstances slightly resembling the circumstances in ["Citizen Kane"], played a prominent part."