<Li> Bernard Fox as the Scottish Shepherd </Li> <P> Written as The Million Dollar Kidnapping, which was used as the shooting title, it was filmed from early October to early December 1970, in the Mexican states of Durango and Zacatecas, including scenes shot at the El Saltito waterfall and Sierra De Organos (in the municipality of Sombrerete, Zacatecas). </P> <P> John Wayne's real - life son, Patrick Wayne, portrays James McCandles in the film, while Robert Mitchum's son, Christopher Mitchum plays Michael McCandles . Wayne's youngest son Ethan Wayne is seen as his grandson, Little Jake, in the movie . </P> <P> Big Jake was released to DVD by Paramount Home Entertainment on April 29, 2003 as a Region 1 widescreen DVD and on May 31, 2011 as a Region 1 widescreen Blu - ray DVD . </P>

Who played john wayne's grandson in big jake