Shep Comes Home (1948)

Little Larry Havens, whose father died in WWII, runs away from home to keep from being separated from "Shep," his father's dog. In Arizona, he is befriended by a kindly Mexican, Manuel Ortiz, who he is able to repay in time, with the aid of Sheriff "Cap" Weatherby, when Ortiz is suspected of crimes committed by local gangsters. "Shep" is instrumental in saving Ortiz from a lynching, and Larry, "Shep" and Ortiz all find a home with a couple they have befriended.