Courage of Lassie

Courage of Lassie is a 1946 Technicolor MGM feature film starring Elizabeth Taylor, Frank Morgan, and dog actor Pal in a story about a collie named Bill and his young companion, Kathie Merrick. When Bill is separated from Kathie following a vehicular accident, he is trained as a war dog, performs heroically, and, after many tribulations, is eventually reunited with his beloved Kathie. Though the film is called Courage of Lassie, and the same dog actor from the Lassie movies is used, Eric Knights fictional canine character Lassie does not appear in the film.

A collie pup is separated from his mother and grows to young adulthood in the forest. After being swept away in a torrent and then shot by a young hunter, he is found by Kathie Merrick Elizabeth Taylor and carried to her home. With the help of a kindly shepherd, Mr. MacBain Frank Morgan, she tends him back to health, names him Bill, and teaches him to herd sheep.One day, unknown to Kathie, Bill is hit by a truck and taken to an animal hospital. Kathie risks her life futilely searching for him on the island where they first met. Bill remains unclaimed in the hospital for two months and is sent to a War Dog Training Center, where he is referred to as Duke. After training, he is shipped out with the troops to the Aleutian Islands Campaign. Duke performs heroically on the battlefield, but the stress and a wound cause him to become aggressive. Sent back to the War Dog Training Center to recover, he escapes, attacking livestock and threatening people as he finds his way back to Kathie. ........

Source: Wikipedia