According to Pilar Wayne Upchurch (John Wayne's former wife), the Duke once played an all-night poker game with the handler who owned Pal (the first screen Lassie) and several other canine actors. "The Duke won all the Lassies," Upchurch recalled. "The next day, the man was devastated. That was his livelihood."
After a good laugh, she added, her husband good-heartedly gave them all back.
[When trainer Rudy Weatherwax acquired Pal (in settlement of a $10 bet), he suffered from mange and distemper, chased cars, and had to be taught to sit and heel. Eventually, however, he sired a long line of celluloid Lassies.]