Question about Carradine

John Carradine was quite wonderful as Casy the ex-preacher. But my question is about another possible Carradine in the movie. In the scene on the porch of the tent-camp when the man is telling them the truth about the flyers advertising work for pickers, there's an older-looking man with a hat standing on the porch with a musical instrument. This man looks identical to the late David Carradine who was only about 4 years old when this movie came out. I was just wondering if this man was a relative of John's like his father or an uncle or something. Anybody know?, because there's not another Carradine listed on imdb besides John as being in this movie.